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White ash
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White ash
White ash
White ash
White ash
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White ash
Fraxinus americana
Also known as: Cane ash
White ash is a species of ash tree native to North America. It’s leaves turn distinctly bright yellow or red in the autumn. Fraxinus americana is a fast-growing pioneer species that often inhabits riparian zones, and fragmented and disturbed habitats. It is similar in appearance to Green ash (F. pennsylvanica) and sometimes it is hard to tell between the two.
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Every 1-2 weeks
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care guide

Care Guide for White ash

White ash prefers moist soil, but it can't tolerate a substrate that remains soggy. Water your plant regularly, especially during prolonged periods of drought. Mulch the area around the tree to help retain moisture.
Fertilization
Fertilization
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Though white ash doesn't demand a fertilizer, it can be fertilized once a year, preferably in the fall. Use a slow-release fertilizer with an equal ratio of nitrogen, phosphorus, and potassium. Spread evenly and water it thoroughly into the soil, following the product's directions.
Trim the dead, diseased, overgrown branches in winter.
Loam, Chalky, Sandy loam, Acidic, Neutral, Alkaline
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Full sun, Partial sun
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Questions About White ash

Watering Watering Watering
Pruning Pruning Pruning
Temperature Temperature Temperature
Seasonal Care Seasonal Care Seasonal Care
How Much Water Do I Need to Water My White ash?
The White ash generally needs about a gallon of water each schedule,With the potted plants, you might want to water them deeply until you see that the water is dripping at the bottom of the pot. Then, wait for the soil to dry before watering them again. You can use a water calculator or a moisture meter to determine the amount you've given to your plant in a week. Provide plenty of water, especially in the flowering period, but let the moisture evaporate afterwards to prevent root rot.

If White ash is planted outdoor with adequate rainfall, it may not need additional watering. When White ash is young or newly planted, make sure it gets 1-2 inches of rain per week. As White ash continues to grow, it can survive entirely on rainfall. Only when the weather is too hot, or when there is no rainfall at all for 2-3 weeks, then consider giving White ash a full watering during the cooler moment of the day to prevent the plant from suffering from high heat damage. Additional watering will be required during persistent dry spells.
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How Often Should I Water My White ash?
The White ash likes deep and infrequent watering. You would want to soak them in a gallon of water each time, especially when they are planted in pots. The water storage of flower pots is limited and the soil will dry out faster. Watering is required every 3 to 5 days when living in a cold region. Water it early in the morning when the soil is dry, outdoors or indoors. You can also determine if watering is needed by checking the soil inside. When the top 2-3 inches of soil is dry, it is time to give the plant a full watering. During hot days, you may need to check the moisture daily, as the heat can quickly dry out the soil in the pot.
Irrigation of the soil is also required if you have a garden. When you live in a hot climate, you might want to water once a week. Only water when you notice that about 2 to 3 inches of soil become too dry outdoors or indoors. Consider the amount of rainwater on the plant and ensure not to add to it to prevent root rot.You may not need additional watering of the plants if there is a lot of rainfall.White ash generally grows during spring and fall. When they are outdoors, you need to add mulch about 3 to 4 inches deep to conserve more water.

You need to water the plants more frequently in sandy soil because this type tends to drain faster. However, with the clay one, you need to water this less frequently where you could go for 2-3 days to dry the plant and not develop any root rot. You could mark the date on the calendar whenever you water and when you notice that the leaves are starting to droop. This can mean that you might be a day late.
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Should I Adjust the Watering Frequency for My White ash According to Different Seasons or Climates?
The White ash needs outdoors come from rain, with only persistent dry weather requiring watering. Throughout the spring and fall growing seasons, the soil needs to be kept moist but not soggy, and alternating dry and moist soil conditions will allow the White ash to grow well. Throughout the summer, hot weather can cause water to evaporate too quickly, and if there is a lack of rainfall, you will need to water more frequently and extra to keep it moist.

Usually, the White ash will need less water during the winter. Since the White ash will drop their leaves and go dormant, you can put them into a well-draining but moisture-retentive soil mixture like the terracotta to help the water evaporate quicker. Once your White ash growing outdoors begins to leaf out and go dormant, you can skip watering altogether and in most cases White ash can rely on the fall and winter rains to survive the entire dormant period.

After the spring, you can cultivate your White ash and encourage it to grow and bloom when the temperature becomes warmer.This plant is not generally a fan of ponding or drought when flowering. You must ensure that the drainage is good at all times, especially during the winter.

When the plant is in a pot, the plant has limited root growth. Keep them well-watered, especially if they are planted in pots during summer. They don't like cold and wet roots, so provide adequate drainage, especially if they are still growing.

It's always best to water your White ash’s diligently. Get the entire root system into a deep soak at least once or twice a week, depending on the weather. It's best to avoid shallow sprinkles that reach the leaves since they generally encourage the growth of fungi and don't reach deep into the roots. Don't allow the White ash’s to dry out completely in the fall or winter, even if they are already dormancy.

Don't drown the plants because they generally don't like sitting in water for too long. They can die during winter if the soil does not drain well. Also, apply mulch whenever possible to reduce stress, conserve water, and encourage healthy blooms.
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What Should I Be Careful with When I Water White ash in Different Seasons, Climates, or During Different Growing Periods of It?
If planting in the ground, White ash mostly relies on rain. However, if there is no rainfall for 2-3 weeks, you may need to give proper consideration to giving the plants a deep watering. If watering White ash in summer, you should try to do it in the morning. A large temperature difference between the water temperature and the root system can stress the roots. You need to avoid watering the bushes when it's too hot outside. Start mulching them during the spring when the ground is not too cold.

The age of the plants matter. Lack of water is one of the most common reasons the newly planted ones fail to grow. After they are established, you need to ease off the watering schedule.

Reduce watering them during the fall and winter, especially if they have a water-retaining material in the soil. The dry winds in winter can dry them out, and the newly planted ones can be at risk of drought during windy winter, summer, and fall. Windy seasons mean that there's more watering required. The ones planted in the pot tend to dry out faster, so they need more watering. Once you see that they bloom less, the leaves begin to dry up.

Potted plants are relatively complex to water and fluctuate in frequency. Always be careful that the pot-planted plant don't sit in the water. Avoid putting them in containers with saucers, bowls, and trays. Too much watering in the fall can make the foliage look mottled or yellowish. It's always a good idea to prevent overwatering them regardless of the current climate or season that you might have. During the months when White ash begins to flower, you might want to increase the watering frequency but give it a rest once they are fully grown.

Give them an adequate amount of water once every 3 to 5 days but don't give them regular schedules. Make sure the soil is dry by sticking your finger in the pot, or use a moisture meter if you're unsure if it's the right time. Too much root rot can cause them to die, so be careful not to overwater or underwater regardless of the climate or season you have in your area.
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What Should I Do If I Water White ash Too Much/Too Little?
An overwatered White ash can start to have leaves that turn yellow, drop off and wilt. The plant can also look dull and unhealthy, with signs of mushy stems. When they are beginning to show these signs, it's best to adjust your schedule whenever possible.
The wilting can also be a sign of under watering as well. You might see that the leaves begin to turn crispy and dry while the overwatered ones will have soft wilted leaves. Check the soil when it is dry and watering is not enough, give it a full watering in time. Enough water will make the White ash recover again, but the plant will still appear dry and yellow leaves after a few days due to the damaged root system. Once it return to normal, the leave yellowing will stop .

Always check the moisture levels at the pot when you have the White ash indoors. Avoid overwatering indoors and see if there are signs of black spots. If these are present, let the soil dry in the pot by giving it a few days of rest from watering.

Overwatering can lead to root rot being present in your plant. If this is the case, you might want to transfer them into a different pot, especially if you see discolored and slimy roots. Always prevent root rot as much as possible, and don't let the soil become too soggy.

You should dig a little deeper when you plant your White ash outdoors. When you check with your fingers and notice that the soil is too dry, it could mean underwatering. Adequate watering is required to help the plant recover.
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What'S the Best Method to Water the White ash?
You might want to put a garden hose at the plant base to ensure that you're promoting excellent root development. Avoid directly spraying the leaves, and know that the leaves will require more watering if they are outdoors and facing direct sunlight. You can also use bubblers that you can put on to each plant to moisten the roots. Also, use soaker hoses that can cover the entire garden or bed when adding or removing plants to push the roots deeply. Drain any excess water and wait for the soil to dry before watering. Water at ground level to prevent diseases. On a sunny day, you might want to spray the entire bush with water. Whether potted or in-ground, please remember White ash prefers deep watering over light sprinkling.
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Why Should I Water the White ash?
Watering the White ash helps transport the needed nutrients from the soil to the rest of the plant. The moisture will keep this species healthy if you know how much water to give. The watering requirements will depend on the weather in your area and the plant's soil.

The White ash thrives on moist soil, but they can't generally tolerate waterlogging. Ensure to provide enough mulch when planted on the ground and never fall into the trap of watering too little. They enjoy a full can of watering where the water should be moist at the base when they are planted in a pot to get the best blooms.

If they are grown as foliage, you need to water them up to a depth of 10 to 20 inches so they will continue to grow. If it's raining, refrain from watering and let them get the nutrients they need from the rainwater.
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pests

Common Pests & Diseases

Common issues for White ash based on 10 million real cases
Brown spot
Brown spot Brown spot
Brown spot
This infection can cause brown spots or patches to appear on the plant.
Solutions: In minor cases of brown spot, there isn’t any need to treat the disease. However, if much of the foliage is affected and defoliation occurs, the plant will benefit from getting rid of the infection. It is recommended to start by applying organic treatment options, working up to the more potent synthetic, chemical fungicides if necessary. Organic options won’t kill the fungus, but will prevent it from spreading. Dissolve ½ teaspoon of baking soda and one teaspoon of liquid soap in a gallon of water. Using a spray bottle, spray on tops and bottoms of leaves until the mixture drips off. Repeat every two weeks until existing spots stop enlarging and new spots no longer appear. Spray a copper-based fungicidal soap on the leaves, coating the top and bottom leaf surfaces. Reapply as directed on the product label. Copper penetrates the leaf surface and prevents germination of spores so the fungus cannot spread. Apply an all-purpose fungicide to the entire plant, following the label instructions carefully.
Caterpillars
Caterpillars Caterpillars
Caterpillars
Caterpillars are fleshy moth or butterfly larvae that come in an array of colors, patterns, and even hairstyles. They chew on leaves and flower petals, creating large, irregular holes.
Solutions: Even though caterpillars are diverse, they all chew on plant parts and can cause significant damage if present in large numbers. For severe cases: Apply insecticide. For an organic solution, spray plants with a Bacillus thuringiensis (Bt), which specifically affects the larval stage of moths and butterflies. Be sure to coat plants, since caterpillars need to ingest Bt for it to be effective. This will not harm other insects. Spray a chili extract. Chili seeds can be cooked in water to make a spicy spray that caterpillars don't like. Spray this mixture on the plants, but be aware it will also be spicy to humans. Introduce beneficial insects. Release beneficial insects to the garden that eat caterpillars, such as parasitic wasps. For less severe cases: Hand pick. Using gloves, pick off caterpillars on plants and dispose of them in a bucket of soapy water. Dust plants with diatomaceous earth. This powder is harmless to humans but irritates caterpillars. Therefore, it will make it difficult for caterpillars to move and eat.
Leaf beetles
Leaf beetles Leaf beetles
Leaf beetles
Leaf beetles are a class of colored insects 1 - 2 cm in size. They gnaw on leaves and petals resulting in small, round holes scattered over the surface.
Solutions: For less serious cases: Remove beetles, nymphs, and eggs. Remove all life stages of the beetles and kill them by placing them in a bucket of warm, soapy water. This can be done more easily by placing the bucket under affected leaves and shaking the plant. This method is most effective in the afternoon when leaf beetles are more active. Always dispose of insects in a sealed bag or container to avoid escape and spread. To treat more serious infestations: Apply organic insecticides. Use naturally-derived insecticides before moving on to synthetic insecticides. Neem oil and pyrethrum are naturally-derived insecticides that should be applied following label instructions. Apply synthetic insecticides. Examples of insecticides effective for leaf beetles include carbaryl, permethrin, and bifenthrin. Apply insecticides according to label instructions.
Black spot
Black spot Black spot
Black spot
Infection by the black spot pathogen causes black spots or patches to appear on leaves.
Solutions: Some steps to take to address black spot include: Prune away any infected leaves, cleaning the pruners between plants with a 10% bleach solution so that the fungus does not spread to healthy leaves. Don't compost pruned plant parts as the spores can linger in the soil for a long period of time - instead, dispose of them in the trash. Use an approved fungicide such as Trifloxystrobin, Chlorothalonil, Maneb, or Myclobutanil. Use a spreader in the fungicide spray to ensure better coverage.
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Brown spot
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Brown spot
This infection can cause brown spots or patches to appear on the plant.
Overview
Overview
Discolored spots on the foliage of plants are one of the most common disease problems people observe. These spots are caused by fungal and bacterial diseases, with most infections related to a fungal pathogen.
Brown spot can occurs on all houseplants, flowering ornamentals, vegetable plants, and leaves of trees, bushes, and shrubs. No plants are resistant to it, and the problem is worse in warm, wet environments. It can occur at any point in the life stage as long as leaves are present.
Small brownish spots appear on the foliage and enlarge as the disease progresses. In severe cases, the plant or tree is weakened when the lesions interrupt photosynthesis or cause defoliation.
Symptom Analysis
Symptom Analysis
In most cases, brown spot only affects a small percentage of the whole plant, appearing on a small amount of the leaves. A small infection only puts minor stress on the plant. However, if left untreated and the disease progresses over numerous seasons, it will severely impact the health and productivity of the infected specimen.
  • Sporulation begins (reproduction of the fungal spores), and tiny spots appear on leaves.
  • Placement is often random and scattered as diseases are spread through raindrops.
  • May appear on lower leaves and the interior of the plant where humidity is higher.
  • Brown spots enlarge and grow large enough to touch neighboring spots to form a more prominent blotch.
  • Leaf margins may turn yellow.
  • Tiny black dots (fruiting bodies of the fungi) appear in the dead spots.
  • Blotches grow in size until the entire leaf is brown.
  • The leaf falls off the plant.
Severe Symptoms
  • Partial or complete premature defoliation
  • Reduced growth
  • Increased susceptibility to pests and other diseases
Disease Cause
Disease Cause
Brown spot, or leaf spot, is a common descriptive term given to several diseases affecting the leaves of plants and trees. Around 85% of diseases exhibiting leaf spots are due to fungus or fungus-like organisms. Sometimes brown spot is caused by a bacterial infection, or insect activity with similar symptoms.
When conditions are warm and the leaf surfaces are wet, fungal spores being transported by wind or rain land on the surface and cling to it. They do not rupture the cell walls but grow in the space between the plant plasma membrane and the plant cell wall. As the spores reproduce, they release toxins and enzymes that cause necrotic spots (i.e., dead tissue) on the leaves, allowing the fungi to consume the products released when the cells degrade.
Solutions
Solutions
In minor cases of brown spot, there isn’t any need to treat the disease. However, if much of the foliage is affected and defoliation occurs, the plant will benefit from getting rid of the infection. It is recommended to start by applying organic treatment options, working up to the more potent synthetic, chemical fungicides if necessary.
Organic options won’t kill the fungus, but will prevent it from spreading.
  1. Dissolve ½ teaspoon of baking soda and one teaspoon of liquid soap in a gallon of water. Using a spray bottle, spray on tops and bottoms of leaves until the mixture drips off. Repeat every two weeks until existing spots stop enlarging and new spots no longer appear.
  2. Spray a copper-based fungicidal soap on the leaves, coating the top and bottom leaf surfaces. Reapply as directed on the product label. Copper penetrates the leaf surface and prevents germination of spores so the fungus cannot spread.
  3. Apply an all-purpose fungicide to the entire plant, following the label instructions carefully.
Prevention
Prevention
Like many other diseases, it is easier to prevent brown spot than cure it, and this is done through cultural practices.
  • Clear fall leaves from the ground before winter to minimize places where fungi and bacteria can overwinter.
  • Maintain good air movement between plants through proper plant spacing.
  • Increase air circulation through the center of plants through pruning.
  • Thoroughly clean all pruning tools after working with diseased plants.
  • Never dispose of disease plant material in a compost pile.
  • Avoid overhead watering to keep moisture off of the foliage.
  • Keep plants healthy by providing adequate sunlight, water, and fertilizer.
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Caterpillars
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Caterpillars
Caterpillars are fleshy moth or butterfly larvae that come in an array of colors, patterns, and even hairstyles. They chew on leaves and flower petals, creating large, irregular holes.
Overview
Overview
Caterpillars can cause problems for home gardeners. If not managed, these insects can defoliate a plant in just a matter of days. However, home gardeners face a challenge because these caterpillars eventually turn into beautiful butterflies and moths, which are important for pollination and the general ecosystem.
There are thousands of different species of caterpillars and many will only target certain plants. If caterpillars are posing a problem, they can be removed by hand, or gardeners can use insect-proof netting to protect their valuable plants.
Symptom Analysis
Symptom Analysis
Caterpillars are the larvae of butterflies and moths. During the warmer months, butterflies and moths that visit gardens will lay their eggs on the underside of leaves.
When the tiny eggs hatch, the young larvae emerge and start feeding on the leaves of the plant. Depending on how many larvae have hatched, they can easily defoliate the plant in a very short period of time. Caterpillars will shed their skin as they grow, around 4 or 5 times during this feeding cycle.
Symptoms of caterpillars eating plants appear as holes in the leaves. The edges of the leaves may be eaten away as well, and flowers can be affected as well.
Some are easy to see, but others need to be searched for. This is because their bodies are often camouflaged to look like part of the plant. Gardeners need to look carefully along the stems of the plant as well as under the leaves. Also, look for tiny white, yellow, or brown eggs that can be found in groups on the underside of leaves.
Once the caterpillar is fully grown, it transforms into a pupa or chrysalis. Then, after a period of time that varies according to the species, a butterfly or moth will emerge from the pupa and the cycle begins again.
Solutions
Solutions
Even though caterpillars are diverse, they all chew on plant parts and can cause significant damage if present in large numbers.
For severe cases:
  1. Apply insecticide. For an organic solution, spray plants with a Bacillus thuringiensis (Bt), which specifically affects the larval stage of moths and butterflies. Be sure to coat plants, since caterpillars need to ingest Bt for it to be effective. This will not harm other insects.
  2. Spray a chili extract. Chili seeds can be cooked in water to make a spicy spray that caterpillars don't like. Spray this mixture on the plants, but be aware it will also be spicy to humans.
  3. Introduce beneficial insects. Release beneficial insects to the garden that eat caterpillars, such as parasitic wasps.
For less severe cases:
  1. Hand pick. Using gloves, pick off caterpillars on plants and dispose of them in a bucket of soapy water.
  2. Dust plants with diatomaceous earth. This powder is harmless to humans but irritates caterpillars. Therefore, it will make it difficult for caterpillars to move and eat.
Prevention
Prevention
Prevention may require less effort than attempts to eradicate infestations that have already begun. Here are our top steps for prevention:
  1. Monitor plants. Check plants regularly for caterpillar eggs on leaves. If they do not belong to an endangered species, they should be squished.
  2. Use insect netting. Cover plants with insect netting to prevent butterflies and moths from laying eggs on plants.
  3. Apply diatomaceous earth. Apply DE to plants early in the season and reapply after rain.
  4. Encourage plant diversity. This will attract predatory insects including parasitic wasps.
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Leaf beetles
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Leaf beetles
Leaf beetles are a class of colored insects 1 - 2 cm in size. They gnaw on leaves and petals resulting in small, round holes scattered over the surface.
Overview
Overview
Leaf beetles range in size from 1.5 mm to 2 cm. Both adult beetles and their larvae eat the leaves of many different types of plants. There are over 35,000 different species of leaf beetles, in a variety of colors including gold, green, yellow-striped, and red striped. Some of these have been mistaken for ladybirds because of their shape and coloring. They can be oval, round, or elongated in shape. These insect pests are most active in spring and summer.
If not controlled, leaf beetles can do a lot of damage to vegetable crops and ornamental plants. They feed on the leaves, flowers, stems, roots, and fruits of different plants. They can fly, which means it's easy for them to move from one plant to another. Some species of leaf beetles only target one specific crop, while others will target many different types of plants. Although a lot of the damage that they cause is cosmetic, an infestation can weaken a plant and leave it prone to other more problematic diseases.
Symptom Analysis
Symptom Analysis
The first signs of a leaf beetles infestation are small visible holes in leaves. Leaves then become discolored and dark beetle droppings can be seen. As the leaves turn yellow and brown, they will drop off the plant onto the ground. Some leaves will appear skeletonized with only the veins still remaining.
Infestation begins in spring, when the adult beetles emerge from the soil and lay their eggs on the leaves of plants. When these eggs hatch, the young nymphs start munching on the leaves as they grow up. Once leaf beetles are large and mature, they'll fall to the ground and pupate in the soil over winter before starting the cycle all over again.
Leaf beetles also eat holes in fruits and vegetables. These can be seen as small round holes that sometimes have a larger brown area surrounding them.
Solutions
Solutions
For less serious cases:
  1. Remove beetles, nymphs, and eggs. Remove all life stages of the beetles and kill them by placing them in a bucket of warm, soapy water. This can be done more easily by placing the bucket under affected leaves and shaking the plant. This method is most effective in the afternoon when leaf beetles are more active. Always dispose of insects in a sealed bag or container to avoid escape and spread.
To treat more serious infestations:
  1. Apply organic insecticides. Use naturally-derived insecticides before moving on to synthetic insecticides. Neem oil and pyrethrum are naturally-derived insecticides that should be applied following label instructions.
  2. Apply synthetic insecticides. Examples of insecticides effective for leaf beetles include carbaryl, permethrin, and bifenthrin. Apply insecticides according to label instructions.
Prevention
Prevention
To prevent infestations of leaf beetles, follow these practices.
  1. Regularly check for beetles. To prevent large pest infestations, be proactive about frequently checking plants for pests and removing them quickly.
  2. Clear debris. Clear weeds and debris to remove areas where these beetles may overwinter and hide.
  3. Attract natural predators. Birds and other insects, such as wasps and ladybugs, are effective natural predators of leaf beetles. Encourage them to visit by including a diverse array of plants to provide habitat and food. Also, avoid applying broad-spectrum herbicides that can harm and kill beneficial insects.
  4. Plant aromatic herbs like mint, garlic, or rosemary, as these can repel leaf beetles.
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Black spot
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Black spot
Infection by the black spot pathogen causes black spots or patches to appear on leaves.
Overview
Overview
Black spot is a fungus that largely attacks leaves on a variety of ornamental plants, leaving them covered in dark spots ringed with yellow, and eventually killing them. The fungus is often simply unsightly, but if it infects the whole plant it can interfere with photosynthesis by killing too many leaves. Because of this, it is important to be aware of the best methods for preventing and treating this diseases should it occur in the garden.
Symptom Analysis
Symptom Analysis
Here are a few of the most common symptoms of black spot:
  • The plant has developed small black spots along the leaves.
  • These spots be small, circular, and clustered together, or they may have a splotchy appearance and take up large portions of the leaves.
  • The fungus may also affect plant canes, where lesions start purple and then turn black.
  • The plant may suffer premature leaf drop.
Though most forms of black spot fungus pose little risk to a plant's overall health, many gardeners find them unsightly. Severe cases can also weaken a plant, so it becomes more susceptible to other pathogens and diseases.
Disease Cause
Disease Cause
Black spot is spread by various types of fungi, which differ slightly depending on whether they are in their sexual or asexual stages.
The fungal spores linger over the winter in fallen leaves and lesions on canes. In the spring, the spores are splashed up onto the leaves, causing infection within seven hours of moisture and when temperatures range between 24 - 29 ℃ with a high relative humidity.
In just two weeks, thousands of additional spores are produced, making it easy for the disease to infect nearby healthy plants as well.
There are several factors that could make a plant more likely to suffer a black spot infection. Here are some of the most common:
  • Exposure to infected plants or mulch (the fungus overwinters on dead leaves)
  • Weakening from physical damage, pest infestation or other infections.
  • Increased periods of wet, humid, warm weather – or exposure to overhead watering
  • Plants growing too close together
Solutions
Solutions
Some steps to take to address black spot include:
  • Prune away any infected leaves, cleaning the pruners between plants with a 10% bleach solution so that the fungus does not spread to healthy leaves.
  • Don't compost pruned plant parts as the spores can linger in the soil for a long period of time - instead, dispose of them in the trash.
  • Use an approved fungicide such as Trifloxystrobin, Chlorothalonil, Maneb, or Myclobutanil.
  • Use a spreader in the fungicide spray to ensure better coverage.
Prevention
Prevention
Here are a few tips to prevent black spot outbreaks.
  • Purchase resistant varieties: Invest in fungus-resistant plant varieties to reduce the chances for black spot diseases.
  • Remove infected plant debris: Fungi can overwinter in contaminated plant debris, so remove all fallen leaves from infected plants as soon as possible.
  • Rake and discard fallen leaves in the fall.
  • Prune regularly.
  • Water carefully: Fungal diseases spread when plants stay in moist conditions and when water droplets splash contaminated soil on plant leaves. Control these factors by only watering infected plants when the top few inches of soil are dry, and by watering at soil level to reduce splashback. Adding a layer of mulch to the soil will also reduce splashing.
  • Grow plants in an open, sunny locations so the foliage dries quickly.
  • Follow spacing guidelines when planting and avoid natural windbreaks for good air circulation.
  • Use chemical control: Regular doses of a fungicide, especially in the spring, can stop an outbreak before it begins.
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distribution

Distribution Map

Habitat

Woods, slopes
distribution map
Native
Cultivated
Invasive
Potentially invasive
Exotic
No species reported
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Plant Type
Plant Type
Tree
Bloom Time
Bloom Time
Spring
Leaf Color
Leaf Color
Yellow
Green
Purple

Name story

White ash
As one of the most common trees in North America, it's also easy to be mixed up with other trees such as green ash (Fraxinus pennsylvanica). Actually, the best way to identify it is to examine its branches and leaves. The back of its leaves features a white covering along its veins, and the surface layer of the branches can be peeled off easily. Although the tree bark is gray colored, the timber turns white after further processing. With these reasons considered, it has been called white ash.

Symbolism

Protection, Prosperity, Sea Rituals, a tie between our world and the spirit world

Usages

Garden Use
White ash is one of the most commonly grown trees, with over 8 billion of them just in the US. Though it is not usually cultivated as an ornamental, it is sometimes planted for its reliably beautiful fall leaves with a lovely gradient of fiery colors. White ash can provide much-needed shade, support a border garden, or simply act as a standalone specimen in the lawn. It works well with forget-me-nots, hostas, and ferns.

Scientific Classification

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White ash
White ash
White ash
White ash
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White ash
Fraxinus americana
Also known as: Cane ash
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Questions About White ash

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Common Pests & Diseases

Common issues for White ash based on 10 million real cases
Brown spot
Brown spot  Brown spot  Brown spot
This infection can cause brown spots or patches to appear on the plant.
Solutions: In minor cases of brown spot, there isn’t any need to treat the disease. However, if much of the foliage is affected and defoliation occurs, the plant will benefit from getting rid of the infection. It is recommended to start by applying organic treatment options, working up to the more potent synthetic, chemical fungicides if necessary. Organic options won’t kill the fungus, but will prevent it from spreading. Dissolve ½ teaspoon of baking soda and one teaspoon of liquid soap in a gallon of water. Using a spray bottle, spray on tops and bottoms of leaves until the mixture drips off. Repeat every two weeks until existing spots stop enlarging and new spots no longer appear. Spray a copper-based fungicidal soap on the leaves, coating the top and bottom leaf surfaces. Reapply as directed on the product label. Copper penetrates the leaf surface and prevents germination of spores so the fungus cannot spread. Apply an all-purpose fungicide to the entire plant, following the label instructions carefully.
Learn More more
Caterpillars
Caterpillars  Caterpillars  Caterpillars
Caterpillars are fleshy moth or butterfly larvae that come in an array of colors, patterns, and even hairstyles. They chew on leaves and flower petals, creating large, irregular holes.
Solutions: Even though caterpillars are diverse, they all chew on plant parts and can cause significant damage if present in large numbers. For severe cases: Apply insecticide. For an organic solution, spray plants with a Bacillus thuringiensis (Bt), which specifically affects the larval stage of moths and butterflies. Be sure to coat plants, since caterpillars need to ingest Bt for it to be effective. This will not harm other insects. Spray a chili extract. Chili seeds can be cooked in water to make a spicy spray that caterpillars don't like. Spray this mixture on the plants, but be aware it will also be spicy to humans. Introduce beneficial insects. Release beneficial insects to the garden that eat caterpillars, such as parasitic wasps. For less severe cases: Hand pick. Using gloves, pick off caterpillars on plants and dispose of them in a bucket of soapy water. Dust plants with diatomaceous earth. This powder is harmless to humans but irritates caterpillars. Therefore, it will make it difficult for caterpillars to move and eat.
Learn More more
Leaf beetles
Leaf beetles  Leaf beetles  Leaf beetles
Leaf beetles are a class of colored insects 1 - 2 cm in size. They gnaw on leaves and petals resulting in small, round holes scattered over the surface.
Solutions: For less serious cases: Remove beetles, nymphs, and eggs. Remove all life stages of the beetles and kill them by placing them in a bucket of warm, soapy water. This can be done more easily by placing the bucket under affected leaves and shaking the plant. This method is most effective in the afternoon when leaf beetles are more active. Always dispose of insects in a sealed bag or container to avoid escape and spread. To treat more serious infestations: Apply organic insecticides. Use naturally-derived insecticides before moving on to synthetic insecticides. Neem oil and pyrethrum are naturally-derived insecticides that should be applied following label instructions. Apply synthetic insecticides. Examples of insecticides effective for leaf beetles include carbaryl, permethrin, and bifenthrin. Apply insecticides according to label instructions.
Learn More more
Black spot
Black spot  Black spot  Black spot
Infection by the black spot pathogen causes black spots or patches to appear on leaves.
Solutions: Some steps to take to address black spot include: Prune away any infected leaves, cleaning the pruners between plants with a 10% bleach solution so that the fungus does not spread to healthy leaves. Don't compost pruned plant parts as the spores can linger in the soil for a long period of time - instead, dispose of them in the trash. Use an approved fungicide such as Trifloxystrobin, Chlorothalonil, Maneb, or Myclobutanil. Use a spreader in the fungicide spray to ensure better coverage.
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Brown spot
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Brown spot
This infection can cause brown spots or patches to appear on the plant.
Overview
Overview
Discolored spots on the foliage of plants are one of the most common disease problems people observe. These spots are caused by fungal and bacterial diseases, with most infections related to a fungal pathogen.
Brown spot can occurs on all houseplants, flowering ornamentals, vegetable plants, and leaves of trees, bushes, and shrubs. No plants are resistant to it, and the problem is worse in warm, wet environments. It can occur at any point in the life stage as long as leaves are present.
Small brownish spots appear on the foliage and enlarge as the disease progresses. In severe cases, the plant or tree is weakened when the lesions interrupt photosynthesis or cause defoliation.
Symptom Analysis
Symptom Analysis
In most cases, brown spot only affects a small percentage of the whole plant, appearing on a small amount of the leaves. A small infection only puts minor stress on the plant. However, if left untreated and the disease progresses over numerous seasons, it will severely impact the health and productivity of the infected specimen.
  • Sporulation begins (reproduction of the fungal spores), and tiny spots appear on leaves.
  • Placement is often random and scattered as diseases are spread through raindrops.
  • May appear on lower leaves and the interior of the plant where humidity is higher.
  • Brown spots enlarge and grow large enough to touch neighboring spots to form a more prominent blotch.
  • Leaf margins may turn yellow.
  • Tiny black dots (fruiting bodies of the fungi) appear in the dead spots.
  • Blotches grow in size until the entire leaf is brown.
  • The leaf falls off the plant.
Severe Symptoms
  • Partial or complete premature defoliation
  • Reduced growth
  • Increased susceptibility to pests and other diseases
Disease Cause
Disease Cause
Brown spot, or leaf spot, is a common descriptive term given to several diseases affecting the leaves of plants and trees. Around 85% of diseases exhibiting leaf spots are due to fungus or fungus-like organisms. Sometimes brown spot is caused by a bacterial infection, or insect activity with similar symptoms.
When conditions are warm and the leaf surfaces are wet, fungal spores being transported by wind or rain land on the surface and cling to it. They do not rupture the cell walls but grow in the space between the plant plasma membrane and the plant cell wall. As the spores reproduce, they release toxins and enzymes that cause necrotic spots (i.e., dead tissue) on the leaves, allowing the fungi to consume the products released when the cells degrade.
Solutions
Solutions
In minor cases of brown spot, there isn’t any need to treat the disease. However, if much of the foliage is affected and defoliation occurs, the plant will benefit from getting rid of the infection. It is recommended to start by applying organic treatment options, working up to the more potent synthetic, chemical fungicides if necessary.
Organic options won’t kill the fungus, but will prevent it from spreading.
  1. Dissolve ½ teaspoon of baking soda and one teaspoon of liquid soap in a gallon of water. Using a spray bottle, spray on tops and bottoms of leaves until the mixture drips off. Repeat every two weeks until existing spots stop enlarging and new spots no longer appear.
  2. Spray a copper-based fungicidal soap on the leaves, coating the top and bottom leaf surfaces. Reapply as directed on the product label. Copper penetrates the leaf surface and prevents germination of spores so the fungus cannot spread.
  3. Apply an all-purpose fungicide to the entire plant, following the label instructions carefully.
Prevention
Prevention
Like many other diseases, it is easier to prevent brown spot than cure it, and this is done through cultural practices.
  • Clear fall leaves from the ground before winter to minimize places where fungi and bacteria can overwinter.
  • Maintain good air movement between plants through proper plant spacing.
  • Increase air circulation through the center of plants through pruning.
  • Thoroughly clean all pruning tools after working with diseased plants.
  • Never dispose of disease plant material in a compost pile.
  • Avoid overhead watering to keep moisture off of the foliage.
  • Keep plants healthy by providing adequate sunlight, water, and fertilizer.
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Caterpillars
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Caterpillars
Caterpillars are fleshy moth or butterfly larvae that come in an array of colors, patterns, and even hairstyles. They chew on leaves and flower petals, creating large, irregular holes.
Overview
Overview
Caterpillars can cause problems for home gardeners. If not managed, these insects can defoliate a plant in just a matter of days. However, home gardeners face a challenge because these caterpillars eventually turn into beautiful butterflies and moths, which are important for pollination and the general ecosystem.
There are thousands of different species of caterpillars and many will only target certain plants. If caterpillars are posing a problem, they can be removed by hand, or gardeners can use insect-proof netting to protect their valuable plants.
Symptom Analysis
Symptom Analysis
Caterpillars are the larvae of butterflies and moths. During the warmer months, butterflies and moths that visit gardens will lay their eggs on the underside of leaves.
When the tiny eggs hatch, the young larvae emerge and start feeding on the leaves of the plant. Depending on how many larvae have hatched, they can easily defoliate the plant in a very short period of time. Caterpillars will shed their skin as they grow, around 4 or 5 times during this feeding cycle.
Symptoms of caterpillars eating plants appear as holes in the leaves. The edges of the leaves may be eaten away as well, and flowers can be affected as well.
Some are easy to see, but others need to be searched for. This is because their bodies are often camouflaged to look like part of the plant. Gardeners need to look carefully along the stems of the plant as well as under the leaves. Also, look for tiny white, yellow, or brown eggs that can be found in groups on the underside of leaves.
Once the caterpillar is fully grown, it transforms into a pupa or chrysalis. Then, after a period of time that varies according to the species, a butterfly or moth will emerge from the pupa and the cycle begins again.
Solutions
Solutions
Even though caterpillars are diverse, they all chew on plant parts and can cause significant damage if present in large numbers.
For severe cases:
  1. Apply insecticide. For an organic solution, spray plants with a Bacillus thuringiensis (Bt), which specifically affects the larval stage of moths and butterflies. Be sure to coat plants, since caterpillars need to ingest Bt for it to be effective. This will not harm other insects.
  2. Spray a chili extract. Chili seeds can be cooked in water to make a spicy spray that caterpillars don't like. Spray this mixture on the plants, but be aware it will also be spicy to humans.
  3. Introduce beneficial insects. Release beneficial insects to the garden that eat caterpillars, such as parasitic wasps.
For less severe cases:
  1. Hand pick. Using gloves, pick off caterpillars on plants and dispose of them in a bucket of soapy water.
  2. Dust plants with diatomaceous earth. This powder is harmless to humans but irritates caterpillars. Therefore, it will make it difficult for caterpillars to move and eat.
Prevention
Prevention
Prevention may require less effort than attempts to eradicate infestations that have already begun. Here are our top steps for prevention:
  1. Monitor plants. Check plants regularly for caterpillar eggs on leaves. If they do not belong to an endangered species, they should be squished.
  2. Use insect netting. Cover plants with insect netting to prevent butterflies and moths from laying eggs on plants.
  3. Apply diatomaceous earth. Apply DE to plants early in the season and reapply after rain.
  4. Encourage plant diversity. This will attract predatory insects including parasitic wasps.
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Leaf beetles
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Leaf beetles
Leaf beetles are a class of colored insects 1 - 2 cm in size. They gnaw on leaves and petals resulting in small, round holes scattered over the surface.
Overview
Overview
Leaf beetles range in size from 1.5 mm to 2 cm. Both adult beetles and their larvae eat the leaves of many different types of plants. There are over 35,000 different species of leaf beetles, in a variety of colors including gold, green, yellow-striped, and red striped. Some of these have been mistaken for ladybirds because of their shape and coloring. They can be oval, round, or elongated in shape. These insect pests are most active in spring and summer.
If not controlled, leaf beetles can do a lot of damage to vegetable crops and ornamental plants. They feed on the leaves, flowers, stems, roots, and fruits of different plants. They can fly, which means it's easy for them to move from one plant to another. Some species of leaf beetles only target one specific crop, while others will target many different types of plants. Although a lot of the damage that they cause is cosmetic, an infestation can weaken a plant and leave it prone to other more problematic diseases.
Symptom Analysis
Symptom Analysis
The first signs of a leaf beetles infestation are small visible holes in leaves. Leaves then become discolored and dark beetle droppings can be seen. As the leaves turn yellow and brown, they will drop off the plant onto the ground. Some leaves will appear skeletonized with only the veins still remaining.
Infestation begins in spring, when the adult beetles emerge from the soil and lay their eggs on the leaves of plants. When these eggs hatch, the young nymphs start munching on the leaves as they grow up. Once leaf beetles are large and mature, they'll fall to the ground and pupate in the soil over winter before starting the cycle all over again.
Leaf beetles also eat holes in fruits and vegetables. These can be seen as small round holes that sometimes have a larger brown area surrounding them.
Solutions
Solutions
For less serious cases:
  1. Remove beetles, nymphs, and eggs. Remove all life stages of the beetles and kill them by placing them in a bucket of warm, soapy water. This can be done more easily by placing the bucket under affected leaves and shaking the plant. This method is most effective in the afternoon when leaf beetles are more active. Always dispose of insects in a sealed bag or container to avoid escape and spread.
To treat more serious infestations:
  1. Apply organic insecticides. Use naturally-derived insecticides before moving on to synthetic insecticides. Neem oil and pyrethrum are naturally-derived insecticides that should be applied following label instructions.
  2. Apply synthetic insecticides. Examples of insecticides effective for leaf beetles include carbaryl, permethrin, and bifenthrin. Apply insecticides according to label instructions.
Prevention
Prevention
To prevent infestations of leaf beetles, follow these practices.
  1. Regularly check for beetles. To prevent large pest infestations, be proactive about frequently checking plants for pests and removing them quickly.
  2. Clear debris. Clear weeds and debris to remove areas where these beetles may overwinter and hide.
  3. Attract natural predators. Birds and other insects, such as wasps and ladybugs, are effective natural predators of leaf beetles. Encourage them to visit by including a diverse array of plants to provide habitat and food. Also, avoid applying broad-spectrum herbicides that can harm and kill beneficial insects.
  4. Plant aromatic herbs like mint, garlic, or rosemary, as these can repel leaf beetles.
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Black spot
plant poor
Black spot
Infection by the black spot pathogen causes black spots or patches to appear on leaves.
Overview
Overview
Black spot is a fungus that largely attacks leaves on a variety of ornamental plants, leaving them covered in dark spots ringed with yellow, and eventually killing them. The fungus is often simply unsightly, but if it infects the whole plant it can interfere with photosynthesis by killing too many leaves. Because of this, it is important to be aware of the best methods for preventing and treating this diseases should it occur in the garden.
Symptom Analysis
Symptom Analysis
Here are a few of the most common symptoms of black spot:
  • The plant has developed small black spots along the leaves.
  • These spots be small, circular, and clustered together, or they may have a splotchy appearance and take up large portions of the leaves.
  • The fungus may also affect plant canes, where lesions start purple and then turn black.
  • The plant may suffer premature leaf drop.
Though most forms of black spot fungus pose little risk to a plant's overall health, many gardeners find them unsightly. Severe cases can also weaken a plant, so it becomes more susceptible to other pathogens and diseases.
Disease Cause
Disease Cause
Black spot is spread by various types of fungi, which differ slightly depending on whether they are in their sexual or asexual stages.
The fungal spores linger over the winter in fallen leaves and lesions on canes. In the spring, the spores are splashed up onto the leaves, causing infection within seven hours of moisture and when temperatures range between 24 - 29 ℃ with a high relative humidity.
In just two weeks, thousands of additional spores are produced, making it easy for the disease to infect nearby healthy plants as well.
There are several factors that could make a plant more likely to suffer a black spot infection. Here are some of the most common:
  • Exposure to infected plants or mulch (the fungus overwinters on dead leaves)
  • Weakening from physical damage, pest infestation or other infections.
  • Increased periods of wet, humid, warm weather – or exposure to overhead watering
  • Plants growing too close together
Solutions
Solutions
Some steps to take to address black spot include:
  • Prune away any infected leaves, cleaning the pruners between plants with a 10% bleach solution so that the fungus does not spread to healthy leaves.
  • Don't compost pruned plant parts as the spores can linger in the soil for a long period of time - instead, dispose of them in the trash.
  • Use an approved fungicide such as Trifloxystrobin, Chlorothalonil, Maneb, or Myclobutanil.
  • Use a spreader in the fungicide spray to ensure better coverage.
Prevention
Prevention
Here are a few tips to prevent black spot outbreaks.
  • Purchase resistant varieties: Invest in fungus-resistant plant varieties to reduce the chances for black spot diseases.
  • Remove infected plant debris: Fungi can overwinter in contaminated plant debris, so remove all fallen leaves from infected plants as soon as possible.
  • Rake and discard fallen leaves in the fall.
  • Prune regularly.
  • Water carefully: Fungal diseases spread when plants stay in moist conditions and when water droplets splash contaminated soil on plant leaves. Control these factors by only watering infected plants when the top few inches of soil are dry, and by watering at soil level to reduce splashback. Adding a layer of mulch to the soil will also reduce splashing.
  • Grow plants in an open, sunny locations so the foliage dries quickly.
  • Follow spacing guidelines when planting and avoid natural windbreaks for good air circulation.
  • Use chemical control: Regular doses of a fungicide, especially in the spring, can stop an outbreak before it begins.
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Plant Type
Plant Type
Tree
Bloom Time
Bloom Time
Spring
Leaf Color
Leaf Color
Yellow
Green
Purple

Name story

White ash
As one of the most common trees in North America, it's also easy to be mixed up with other trees such as green ash (Fraxinus pennsylvanica). Actually, the best way to identify it is to examine its branches and leaves. The back of its leaves features a white covering along its veins, and the surface layer of the branches can be peeled off easily. Although the tree bark is gray colored, the timber turns white after further processing. With these reasons considered, it has been called white ash.

Symbolism

Protection, Prosperity, Sea Rituals, a tie between our world and the spirit world

Usages

Garden Use
White ash is one of the most commonly grown trees, with over 8 billion of them just in the US. Though it is not usually cultivated as an ornamental, it is sometimes planted for its reliably beautiful fall leaves with a lovely gradient of fiery colors. White ash can provide much-needed shade, support a border garden, or simply act as a standalone specimen in the lawn. It works well with forget-me-nots, hostas, and ferns.

Scientific Classification

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