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Who Is Most at Risk of Plant Poisoning?

When it comes to humans, the dangers of plant poisoning will usually fall upon everyone, especially those who spend a lot of time outside. Those include outdoor workers, hikers, foragers, and children. While each group is exposed to toxic plants, they are usually affected differently.

Outdoor Workers and Recreationalists

Those who enjoy the outdoors either as a hobby or as part of their work will rarely see a plant and decide to munch on it (although the scenario is not unheard of). However, they do tend to deal with moving through and brushing aside plants. These people are more at risk of being poisoned by touching toxic plants than by ingesting them.

Foragers

Foraging for food and medicinal plants is a desirable skill among people who want to feel at one with the land. This hobby can be very useful and enjoyable, but if done wrong , it can lead to disastrous effects. People who forage are picking and grabbing plants with the full intention of using those plants, most of the time to ingest them.

When done correctly there is nothing wrong with this practice. However, when attempting to do this it is important to gain advice from an advanced forager. The reason is that many good plants have family members that look alike and are extremely poisonous or even deadly. Tomatoes, peppers and other nightshades are examples of plants with toxic lookalikes.

Even some of the plants that people intentionally forage can be toxic if not processed properly. It is important to always double-check! Better safe than sorry.

Children

While outdoor workers are more likely to touch poison and foragers are more likely to ingest poison, children can easily do both. These bundles of joy just love to run around and explore the world. They enjoy touching things and occasionally shoving random stuff in their mouth; this is a terrible combination with toxic plants in the mix.

If you let your children run about, it is important to know what are the local toxic plants that they could accidentally get into. Try to educate the children and steer them away from where the toxic plants are located.

It is important to note that humans are not the only ones susceptible to toxic plants. Animals can be just as likely to happen upon poisonous plants.

Pets

Some pets are less likely than children to eat and touch just about everything. This is good, as a pet owner. However, you know your pet best, and it is up to you to keep them safe. There are plenty of poisonous weeds that can grow within the confines of your lawn, which might make your dogs or cats ill or worse if they eat them. Try to have an idea of what toxic plants grow in your area and keep them under control and your pets away from them.

The Common Symptoms of Plant Poisoning

There are many ways that a plant can pass on its toxic compounds. Some toxins can be produced and exuded through the plant’s leaves, leaching toxins through touch or even the air, while others need to be ingested. We will explore all of these methods and explain some of the symptoms associated with them.

Poisonous to Touch

Many people in the United States are familiar with the infamous names poison oak and poison ivy. These two species of plants are known for their itch-inducing leaves, and are usually shown to children who are going on camping trips to help them avoid the nasty side effects of touching these plants.

They are perfect examples to show you how these types of poisonous plants work. They produce oils that stick onto their leaves. When someone, unaware of the danger, touches the leaves, the oils stick to the skin and do all of the dirty work. In the case of poison ivy, urushiol oil reacts with your skin, causing an allergic reaction. You will generally experience skin swelling, redness, itchiness, and blisters.

In the case of poison ivy and poison oak, the U.S. government has documented steps on how to treat blisters and swelling caused by these plants, which can be accessed here: Poisonous Plants: Symptoms and First Aid. Of course, if you are ever in doubt, it is always good to call your local center for poison control.

Another reason why it is important to always know what types of plants you encounter and what to do in an emergency: the giant hogweed (Heracleum mantegazzianum). This plant has a sap that, given the right conditions, will give humans severe, third-degree burns. Remember — it is always better to prepare by knowing and avoiding these plants than to deal with the effects of coming in contact with them.

Poison by Ingestion

This is another reason why it is very important to know the types of plants you are working with and whom to contact in an emergency. It is always better to prepare by knowing and avoiding these plants beforehand than to deal with the side effects of touching them.

Another common yet toxic plant is poison hemlock. This plant belongs to the carrot family but doesn’t like to be eaten as much as its orange relative. When ingested, it can cause damage to your kidneys and nervous system in addition to slowing your heart rate.

As you can imagine, these side effects are no joke. It is important to get the proper medical attention immediately if you even suspect that you or someone you know may have consumed these plants or are experiencing these symptoms.

Never be afraid to call poison control if the situation doesn’t merit an ambulance. Poison control can help manage symptoms and identify when medical attention is necessary. A lot of these symptoms seem scary, and they are, which is why it helps to recognize who is most at risk and what plants will endanger them.

Why Are Some Plants Toxic?

Have you ever been scared enough that the hairs on the back of your neck stand up? Fear comes in many forms, and people experience it in different ways. Terror of “monsters” such as wild cats, wolves, or bears lurking in the dark can stop one from walking in the wild alone. Plants, seemingly innocent, very seldom make the top of anyone’s list of fears.

Plants are generally seen as good, being associated with “going green” and bodily health. These associations can be quite deceiving, since many plants are extremely toxic. Even those that aren’t toxic may mimic or be similar in appearance to other plants that are toxic, increasing the likelihood of making a fatal mistake. This knowledge is powerful, and shouldn’t be taken lightly.

Knowing what plants are toxic and how to approach them is very important, and will be one of the topics that we discuss. First, we are going to take a step back and understand exactly why some plants are toxic.

Evolution

According to Darwinism, life since the beginning has been a fierce battle of survival of the fittest. Thanks to malfunctions in genetic duplication and reproduction processes, life has diversified time and again. This has allowed single-cell organisms turn into multi-cell organisms, and multi-cell organisms to diversify even further into kingdoms such as plants, animals, and fungi.

These little mistakes in the genetic duplication process are known as mutations. They are what fuel the ever-changing evolutionary process. While most of these mutations are not beneficial, those that are helpful stick around, since they help their species live longer lives and reproduce. Reproduction is the name of the game for these mutations. If they are able to help their species reproduce, they have accomplished their goal, and ensured that they are passed onto the next generation.

Each kingdom is unique in the way that it plays the game of life — and that’s only the beginning. Every species in each kingdom is wildly different. For the plant kingdom, surviving until reproduction can be a challenge since most plants are immobile. The plants need to go through the energy-taxing experience of seed production all while standing out in the open, hoping predators don’t decide they are a tasty snack.

This is where the handy mutation of toxicity comes into play. Simply put, all plants use DNA to produce proteins that will help perform the functions of life. When plants are consumed, the proteins within the plant are digested. Many plants are perfectly digestible, but due to random happenstance, when DNA was copied for reproduction in certain plants, it copied wrong. When these plants with the new genes sprouted, their DNA coded entirely different proteins, which just so happened to be toxic.

This accident caused these plants to perform better than their contemporaries, allowing them to pass on the new, toxic genetic trait. This is the main reason why a lot of plants are toxic. They develop their toxic traits by accident, and because those traits help them perform better they stick. They pass along the trait to their offspring. It is important to point out that even though some plants are toxic to certain species, that is not always an indicator that they will be toxic to humans.

However, it is very important to know what the common symptoms of plant poisoning are, which we will go over now.

Common Pests Affecting Trees and How to Treat Them

Boring Insects

Of the three insect types, boring insects have the highest potential of causing severe damage or even death to trees. These insects live inside the stems, roots, and branches of a tree and cause damage by tunneling through and feeding on the tissues of the tree. Aside from the damage caused by feeding, these tunnels prevent the tree from circulating water properly, which can starve it of necessary moisture and nutrients.

Borers can be from a wide range of insect species, generally some type of weevil, caterpillar, or beetle. Some typical examples of boring insects are the wood-boring moth caterpillar, bronze birch borer, dogwood borer, elm bark beetle, emerald ash borer, and giant palm weevil. Some species of insect live in trees only during their larval stage.

You can identify the symptoms of a boring insect by checking the tree for the holes left behind in the bark and the presence of insect waste that looks like sawdust at the base of the tree. Ideally you will notice these signs early, before the insects have a chance to cause serious issues. If the damage is severe and the vascular system has been affected, there may be portions of the crown that are wilting and dying. Some trees exhibit cracked bark or dying limbs because of the lack of nutrients.

Prevention

If you know there are specific wood-boring insects common in your area, you can choose tree species that are less susceptible to attack. Regardless of the tree type, you can help prevent infestation by keeping the tree as healthy as possible. Limit pruning to the late fall or winter, as this timing minimizes the chances of insects making their way into the open wound. Likewise, it is important to avoid accidentally damaging the tree when doing lawn care or other activities nearby. Any wound can make the tree vulnerable to boring insects. Also be sure that you remove any fallen branches from your yard as soon as possible, as these insects can easily enter dead and decaying wood.

Treatment

Depending on the type of insect, a systemic or contact insecticide can be used to kill insects and prevent future attacks. You may need to remove part or all of the tree if the infestation is severe.

There are a variety of insects that live in trees, and the majority of them are not harmful. But a few types of insects can cause significant damage, or even death, to your trees if they are left untreated in your yard. In general, tree pests are divided into three categories: chewing insects, sap-sucking insects, and boring insects.

Chewing Insects

Chewing insects feed on the foliage or fruit of trees. Those that only feed on leaves are also called defoliating insects. They can be highly destructive and are especially devastating to fruit crops.

One of the most common defoliating insects is the gypsy moth, which attacks many types of common hardwood trees such as oak, birch, apple, willow, elm, and maple. Other typical chewing insects include bagworms, Japanese beetles, apple maggots, cherry fruit worms, tent caterpillars, and leafminers.

The symptoms of chewing insects are curling or ragged leaves with holes, and brown spots on fruit where the insects have penetrated the protective skin. Some insects consume every part of the leaf except the veins — a process called skeletonization.

Prevention

A healthy, mature tree can usually withstand quite a lot of defoliating insects, and keeping your tree healthy is the best preventative measure against this and all types of pests. A sticky or slippery barrier can interrupt the movement of crawling insects such as caterpillars, preventing them from reaching the leaves.

Treatment

It is best to avoid chemical treatments for tree pests if possible, but jojoba or neem oil are plant-based treatments that kill chewing insects on contact with few side effects. Insecticidal soap also breaks down quickly and is generally considered safe to use.

Sucking Insects

Sucking insects feed on the liquid in leaves, twigs, and stems. Some types remain immobile, and blend in with their surroundings, while others move around continuously to feed on different parts of the plant. Common sucking insects found on trees include scale insects, aphids, leafhoppers, spider mites, and thrips.

To identify the presence of sucking insects, look for the sticky substance (honeydew) they leave behind. Honeydew can also attract sooty mold on leaves. Scale insects, leafhoppers, and aphids are generally large enough to be seen with the naked eye, while spider mites and thrips are tiny and can usually only be identified by other signs of their presence. You might also see spots or streaks on the leaves where insects have fed on them.

Prevention

As with other insect types, a healthy and mature tree is much less likely to fall victim to sucking insects, so try to follow proper watering, pruning, fertilization, etc., to keep your trees in top condition. Horticultural oil works as a preventative during the winter, as it kills hibernating insects in trees during the dormant season.

Treatment

Horticultural oil and insecticidal soap can be effective against a variety of sucking insects. If the infestation is not extensive and is isolated to one part of the tree, you may be able to prune off affected areas.

Troubleshooting Tree Diseases

Trees are susceptible to a variety of diseases, and they can cause symptoms ranging from mild leaf damage all the way to killing the tree completely. In general, the best way to prevent tree disease is to keep the tree healthy, as healthy trees are able to recover from disease more easily than stressed trees.

You can prevent many fungal diseases by removing yard waste in the fall, so new leaves aren’t exposed to the spores when they emerge in spring. Since there are many tree diseases, this article will just cover some of the most common ones. Be sure to consult a professional about your diseased tree to make sure you are using the correct treatment method, as symptoms look similar for many conditions.

Foliar Diseases

Anthracnose (leaf blight)

This fungal disease attacks leaves and sometimes stems of deciduous trees such as ash, maple, hickory, walnut, and birch. Leaves appear blotchy and scorched, with some dead spots. Damage can be severe but is rarely fatal.

Rusts

Leaf rusts are common on trees such as poplar, willow, ash, birch, maples, and cottonwoods. This group of fungi are classified in the order Pucciniales, and there are around 8000 different species of rust fungi. Many of them are specific to just one or two types of host plant. The main symptom of leaf rust is the presence of yellow-orange (sometimes brown or red) powdery spots on the leaf surface. Rusts can cause leaves to drop, which affects overall growth, but they are rarely fatal.

Powdery Mildew

This fungal disease (mainly from the genus Microsphaea) causes white powdery spots on tree leaves, and is most common during the hottest and driest months of the summer. Powdery mildew can be controlled with chemical treatments if the disease is severe.

Stem Diseases

Cankers

Several types of fungus can cause cankers (for example chestnut blight, Nectria canker, Phytophthora dieback, and Cytospora canker). They occur when some damage occurs to the tree, such as a branch breaking off in a storm. This open wound allows the fungus to attack the tree during its dormant period, leaving behind areas of dead bark and wood. Some cankers are localized to a certain area, while others can spread throughout the tree with potentially lethal results. A branch with a canker can be pruned, but if the canker is on the trunk, the tree should likely be removed entirely.

Wilts

Wilt fungi (including oak wilt, verticillium wilt, and Dutch elm disease) block the water flow within a tree’s tissues, meaning that moisture cannot reach the leaves. Leaves appear scorched but don’t drop off the tree. A systemic fungicide may be effective against wilt, but often trees die too quickly for treatment to be applied.

Root Diseases

Root Rots

When fungi such as white root rot (Corticium galactinum) and Texas root rot (Phymatotrichopsis omnivorum) attack tree roots, the tree is no longer able to absorb water and nutrients from the soil. Unfortunately, it’s difficult to notice root diseases since they are underground. It is most likely in trees growing in soil that is too wet and doesn’t drain well. Symptoms are slow growth, wilting leaves, early leaf drop, and sometimes death of the tree.

Pruning Trees

There are plenty of trees that go their whole lives without ever being pruned, of course, but pruning can certainly be beneficial depending on the type of tree, its condition, and your specific goals. Some trees can be pruned easily with regular garden tools, but larger jobs may need the assistance of a professional to do it safely and correctly.

Why and When Do Trees Need To Be Pruned?

Removing dead or dying branches has several important benefits for trees. First, unhealthy branches consume energy that could otherwise be used by the tree to create new growth. If there are diseased branches on your tree, it is often easier and more effective to remove those affected branches rather than trying to treat the disease. Dead or damaged branches also run the risk of falling off and damaging property or even an unlucky person who might be walking below.

Removing some branches also helps with air circulation and sunlight exposure for the rest of the tree, making it healthier overall. It can help keep the tree to a manageable size, and improve the appearance of the tree by keeping it compact and well-shaped. Finally, pruning fruit trees encourages fruit production the following year.

You can prune off dead or damaged branches at any time of year, but choose a day without precipitation or high humidity since fungus can be spread by moisture in the air, causing disease. For other types of pruning, late winter or early spring is generally the best time of year as it reduces the risk of infection and disease, and allows the tree to put out lots of vigorous growth in spring.

Steps to Pruning a Tree

Decide where to cut. You need to have a plan in order to correctly plot and decide what tools to use. You may want to mark the branches with a string or tape so you don’t forget your plan midway through.
Gather your tools. If there are just a few small branches to prune, you might be fine with a set of pruning shears or loppers. For a larger job, a pole saw is the better option. Be sure to also have eye protection, gloves, and protective clothing to avoid injury.
Identify the branch collar. The branch collar is a thickened area where the base of a branch meets the trunk. The best way to prune a branch is to cut next to the branch collar without damaging it. This allows the wound to callus over properly, protecting the tree from insects and disease. To prune partial branches, make your cut just below a node.
Cut at a 45-degree angle. Cutting at a downward angle prevents water from collecting on the stump, which can cause rot. Be sure to cut only the branch, without damaging the trunk.

After pruning, clean up the waste that has been removed. If the tree was diseased, dispose of the branches in the garbage. Healthy yard waste can be repurposed for mulch or used in compost.

How Do Seasons Affect Trees?

Like all outdoor plants, trees that live in climates with changing seasons have evolved to adapt to seasonal changes in order to survive. Different types of trees may have different adaptations (deciduous vs. evergreen trees, for example), but all varieties make some subtle adjustments.

Spring

Warmer temperatures and longer days trigger trees to become active again after the long period of winter dormancy. As snow thaws and rainfall increases, tree roots are able to access more water and nutrients from the soil. More moisture in the tree stimulates the production of sap that delivers necessary nutrients for leaves and flowers to be produced.

Summer

During summer, leaves are at their maximum size and quantity, allowing the tree to make the most of the long daylight hours for photosynthesis to create energy. This makes summer the season with the maximum growth, when a healthy tree will expand in both height and width.

Be aware that unusually high temperatures, intense sunlight, and lack of precipitation can damage trees or cause them to pause photosynthesis in order to preserve energy until conditions become more favorable. Be sure to keep trees watered during hot and dry summer days.

Autumn

During autumn, the amount of sunlight decreases, and this signals to the tree that it is time to prepare to enter a dormant stage for the winter. For many varieties of trees, this means leaves change color and drop off. As they lose their chlorophyll, other colors such as red or yellow become visible. Meanwhile, conifers have a different evolutionary strategy. Because their needles lose very little water to the dry winter air, these trees can actually conserve energy by not dropping many of them during the winter.

Winter

With preparations completed during the autumn, trees enter their dormant period over the winter. During this time, they slow or stop the processes of photosynthesis, growth, and reproduction. Trees depend on energy stored inside their cells at this time, since they are not generating any during dormancy.

Trees also have to deal with a lack of water over the winter, so they produce special proteins that work within cells to prevent them from freezing. Snow, ice, and storms can damage trees during the winter, leaving behind wounds that may be vulnerable to fungal or bacterial infection spread by insects.

Preparing Trees for Winter

To get your trees ready for winter and keep them as healthy as possible until the weather gets warm again, there are a few steps you should take:

Prune: Remove any dead or unhealthy branches from your tree. This allows your tree to redirect its energy to new growth and minimizes the chances of branches breaking off over the winter.
Add mulch: A layer of mulch around the base of your tree helps the roots retain a more consistent temperature, and retains moisture in the soil.
Water: Watering your trees after you mulch provides them with much-needed moisture to sustain them through dry winter months.
Wrap the trunk: Wrapping vulnerable trees with a tree-wrap material protects them from temperature fluctuations and storm damage. Wrapping the trunk from top to bottom prevents water from collecting in the folds.

Fertilizer, Insecticide, and Fungicide Treatments

Fertilizer

Before talking about fertilizing trees, it may be useful to cover what fertilizer is (and what it isn’t). Fertilizer isn’t food for plants, nor is it medicine. Instead, you can think of it as more like a vitamin to support the tree’s growth and development.

The only way to know for sure what’s in your soil is to have it tested. Soil tests generally tell you the pH of the soil plus what nutrients are available in the soil to be used by plants. If some minerals are insufficient in the soil, fertilizer can be applied. However, it is important not to add in nutrients that are already abundant in your particular soil composition. Too much of any of the nutrients can cause fertilizer burn in your trees.

The three major components in fertilizers are nitrogen, phosphorus, and potassium, designated with the letters NPK on labels. Secondary nutrients such as calcium, magnesium, and/or sulfur may also be included in commercial fertilizers.

If you fertilize your lawn, you’ll also be fertilizing nearby trees, so be careful not to overdo it. Use your soil analysis to understand what ratio is best. For example, if your soil is low in nitrogen, you might choose a 3:1:1 NPK fertilizer as it has three times as much nitrogen as the other two nutrients.

Insecticides

Insecticides (also called pesticides) are used to kill insects that feed on trees. A healthy, mature tree can endure a certain amount of insect pests, so only use an insecticide if it’s truly necessary. The most common use for an insecticide is on fruit trees, but other kinds of insect infestations can damage or even kill trees.

Insecticides can be applied in the form of a foliar spray or a systemic treatment. Foliar spray is sprayed on the leaves and branches of a tree, while a systemic insecticide would be applied through absorption from the soil or, in some cases, by injecting the tree. Systemic insecticides are generally preferable, since spraying trees is difficult and messy. Foliar sprays can also affect areas other than your tree, and may inadvertently kill beneficial pollinators like bees. Systemic insecticides only affect those insects that are actively feeding on the tree.

Be sure to read all instructions before using an insecticide. Make sure it is safe for the tree and is the right one to use for the pest you are trying to treat. Also confirm the correct time of year and ideal environmental conditions before applying it.

Fungicides

As with insects, there are many types of fungi that may appear on your trees, and not all of them are harmful. However, if your tree has a fungal disease, your best course of action is generally to apply a fungicide. As with pesticides, both foliar and systemic fungicides are readily available.

The most important thing before treating your tree for fungal disease is to correctly identify the issue. Not all fungicides treat every type of fungus, and many types of fungal and bacterial diseases can look similar.

Since fungus travels around via spores that float in the wind, it can move quite easily from one tree to another. Even if you don’t see evidence of the fungus on more than one tree, you may want to treat all the trees in the area with fungicide as a preventative measure. Always read the label on your fungicide carefully and follow the instructions for proper application.

Common Fence Garden Problems

Growing a garden near a fence presents a few specific challenges that are not common in other growing locations. In this chapter, we’ll help you become aware of a few of the most prevalent fence-garden problems so that you are well prepared to prevent them.

Plants Intertwining with Fences

Some plants, especially vigorous climbing vines, can become intertwined with certain fence types. At times, this intertwining can be so severe that it becomes impossible to remove the plant from the fence. This issue can become quite costly as you may need to remove the entire fence to remove the plant causing the issue. Chain-link fences are most susceptible to this problem, but any fence with gaps can allow vines to twist through them, to the point where the fence and the vine nearly become one.

Plants Growing into Neighboring Properties

Many fences mark the division of two separate properties. If this is the case for your fence, you must be wary of the fact that your plants can grow so large that they reach over your fence and into your neighbor’s property. Allowing your plants to grow beyond your property is not only a bit intrusive, but it also may make more garden maintenance work for your neighbors. As such, it’s most sensible to monitor the size of your plants to ensure that they never come close to encroaching on your neighbor’s property.

Structural Damage from Invasive Roots

Occasionally, the roots of your fence-garden plants can cause complications for your fence. This is most common with plants that have invasive roots that are strong and spread quickly through the soil. Such plants are often capable of compromising any underground structures that support your fence. The same problem can occur with other structures, including house foundations. When unexpected, this problem can ruin these structures beyond repair. The best way to avoid this issue is to know what plants are most likely to have invasive roots and to plant them far enough away from your fence that damage is unlikely.

Seasonal Maintenance for Fence Gardens

When growing a fence garden, there are plenty of seasonal tasks that you’ll need to attend to in order to keep your plants in their best condition. In this chapter, we’ll reveal a few of the most crucial of these tasks, some of which will boost your plant’s health while others will improve their appearance.

Deadheading Flowering Fence Plants

If you grow flowering plants near your fence, it’s wise to deadhead these plants most years. Deadheading is a type of pruning in which you remove any spent blooms that remain on the plant. The main advantage to deadheading is that it often encourages your plants to bloom more vigorously in the future.

Cutting Back Plants Seasonally

Our next seasonal maintenance task for fence gardens is one that will ensure that your plants do not grow beyond your control. Whether you grow fast-growing vines, large shrubs, or any other significant plant, you’ll likely need to cut them back to a manageable size each year to ensure they do not overcrowd your fence or overtake nearby plants.

Pruning for Size and Shape

Pruning is not only a functional task that encourages your plant to grow more healthily. It is also a way to ensure your garden achieves your personal aesthetic goals. When pruning, you can focus on making cuts that emphasize the plant’s natural form. Alternatively, you can prune some plants into specific shapes, an approach that is especially common for evergreen shrubs.

Rejuvenation Pruning

Rejuvenation pruning is a more extreme form of pruning that you should use when your plants have become overgrown or taken on an unshapely form. To perform this kind of pruning, you’ll need to cut your plant nearly all the way back to the ground, leaving stems that are just a few inches long. After you make these cuts, the plant will begin growing again, allowing you to control its shape once more.