What are aphids and spider mites and what do they do?

Aphids and spider mites are very different pests, but they share some similarities. Aside from being very tiny and very destructive, they’re very different in terms of identifying characteristics and the type of damage they cause. Aphids are very tiny bugs that feed off of the sap in your plants’ leaves. Spider mites, on the other hand, are teeny little arachnids that chew on the leaves themselves. Aphids are about 1/4″ in length, and they can be black, brown, grey, yellow, white, or light green. Spider mites are even smaller, at around 1/50″ in length, and they’re typically a reddish brown hue.

What types of plants are at risk?

Since aphids and spider mites feed on a variety of plants, they’re happy to move from one plant to the next in your yard. They form colonies that cluster together on the underside of leaves, which causes your plants to become weakened. Nearly all plants are at risk of attracting aphids and spider mites, and these pests are most active during the spring and summer months.

How do you detect aphids and spider mites?

Since they’re so tiny, it can be difficult to see aphids and spider mites until your plants begin to show damage. If you suspect that these pests are present, grab a magnifying glass and closely inspect your plant’s leaves. Aphids usually hang out near the leaves, stems or buds of your plants, and they leave a sticky residue behind that’s called honeydew. Ants especially love to eat honeydew, so if ants are present, you’ve probably got an aphid problem.

Spider mites can be found on the underside of leaves, and they create webbing that can reach from the leaves to the stem of your plants. This webbing can also stretch from one plant to another as spider mites travel. Another sign of spider mites is small holes on the leaves of your plants.

If an infestation persists, leaves will begin to turn yellow, and they’ll eventually fall off.

What are the best treatment options?

Here are some of the most effective ways to get rid of aphids and spider mites.

Aphids

• Spray leaves with cold water several times a day.
• Apply insecticidal soaps, horticultural oils, or neem oil to the leaves of affected plants.
• Spray leaves with a mixture of 1 quart water to 1 tsp dish soap several times a day for two weeks.
• Use pesticides for severe infestations.

Spider Mites

• Isolate the affected plants so they don’t spread.
• Spray the leaves and stems with water several times a day.
• Introduce neutral predators like ladybugs and other parasitic mites.
• Apply neem oil or insecticidal oil to the leaves.
• Apply insecticidal soaps that list potassium as the main ingredient.

Aphids and spider mites are very common pests that affect most plants and trees in the Denver area. They’re hard to spot, but without proper treatment, these tiny pests can wreak havoc on your plants. If you suspect an aphid or spider mite infestation, or if you’d like more information about how to keep your plants safe from pests, contact us today. Our experts at American Arbor Care would be happy to help.

Denver winters are known for being very cold, and most plants have adapted to snowy conditions. Although the temperatures typically remain below freezing from late fall to early spring, it’s not uncommon for the area to experience warm, dry periods as well. Although warm and sunny temps may feel fantastic, they can lead to winter droughts that are harmful to plants. Let’s look at how to water your plants throughout the winter months so they are healthy and strong in the spring.

When Should I Water Plants in the Winter?

Colorado winters have a reputation for being cold and snowy, but that’s not always the case. Dry spells are common, and temperatures can fluctuate from very cold to sunny and mild. Snow and ice will melt and water your plants, but when temperatures are dry for a number of weeks, it’s important to water them. Dry periods can quickly become droughts for plants, and irregular watering can lead to weakened root systems. If there has been no precipitation for at least three weeks, it’s best to water your plants thoroughly. This will prevent root damage from occurring as a result of winter drought conditions, and your plants will thank you when spring arrives.

Make sure that when you water your plants, the temperature is above 40° F and the ground is not snow-covered. Frozen soil can’t absorb water, so it’s best to wait for the temperatures to warm up a bit. Water at the warmest time of day to ensure that temperatures remain above 40° F as the water soaks into the soil.

How Should I Water Plants Effectively in the Winter?

Water trees at the drip line, where the farthest ends of the branches would drip onto the ground. That way, the entire root system will get the water it needs. It’s also important to water about halfway from the drip line to the trunk of the tree. Trees require about 10 gallons of water for each inch of the trunk’s diameter, and a shrub needs 5 to 18 gallons of water, depending on its size.

Water your plants early in the day, when the sun is warmest, so the moisture has enough time to fully soak into the soil. If you wait too long, nighttime temperatures can dip below freezing, making it difficult for water to reach the roots.

Additionally, waterin when temperatures dip too quickly, can result in frost/freeze cracking.

You can also add a layer of mulch around the base of your trees and shrubs, to encourage better watering, and to provide protection to the roots underneath the soil.

What Plants Need Water Most in Winter?

Most trees and shrubs go into dormancy during the winter, but their roots continue to grow. This means they still need water to survive, or they’ll be weakened when spring arrives. Trees and shrubs that need water the most in Denver winters include evergreens, conifers, and plants with shallow roots like lindens, birches, and Norway and silver maples. Recently transplanted plants should also be watered regularly.  Evergreens and broadleaf evergreens on warmer days also benefit from foliage baths to increase humidity.

A Few Precautions

Freezing temperatures can lead to burst pipes and broken attachments, so it’s important to take precaution when watering plants in the winter months. When you’re finished using the hose, disconnect it from the spigot and drain it thoroughly. Otherwise, water inside the hose can freeze, causing it to crack, and your pipes can freeze, leading to disaster.

It’s also best not to use your sprinkler system during the winter months. Frozen water expands, and it can easily break attachments and water lines, which can mean expensive repairs in the spring.

If you’d like to learn more about caring for your plants during the winter months, contact us today. Our experts at American Arbor Care would be happy to help you ensure that your plants are healthy year-round.

Aspen trees are known for their beautiful trunks and magnificent foliage, and it’s no wonder that many people consider adding them to their home landscapes. However, before you head out to your nearest nursery, it’s important to learn about an aspen’s needs, so you can determine whether it will thrive in your unique yard, soil, and climate.

What Do Aspen Trees Look Like?

Aspens are easily identified by their bright white bark that’s dotted with black scars where branches have been self-pruned along its lower trunk. Golden heart-shaped leaves contrast with the white bark, making these trees a fan favorite for home landscaping purposes. Unfortunately, aspen trees don’t grow particularly well in every region.

Where Do They Grow?

Aspens have learned and adapted to grow in many regions, but they prefer gravelly soil that’s acidic, well-drained, and moist. This type of soil is most common in higher elevations. Here, in Denver, the soil is much different. Our soil is more alkaline (meaning it has a higher pH), and it contains more clay. This makes drainage more difficult, and fragile roots have more trouble reaching to find a water source. Denver’s climate is also drier and hotter than aspens prefer, making it more difficult for them to grow and thrive in our region. 

Although Denver’s soil and climate are not an ideal environment for aspen trees to grow, they can successfully thrive in our region — with a lot of help.

How Do They Grow?

Aspens are truly remarkable trees. In fact, one tree is just a small part of a larger organsim, called a stand. A stand of aspens is considered the world’s largest living organism, with a main life force of roots connecting all of the trees below ground. The stand of aspens in Utah’s Fishlake National Forest has been in existence for over 80,000 years, and it’s the world’s oldest — and heaviest — living organism. 

These stands (or clones) reproduce new aspen trees by sending up sprouts from the roots, and each new tree is a genetic replicate of all the growing nearby. 

How Long Do They Live?

In ideal climates, aspen trees can live for 150 to 200 years. In Denver, their life expectancies aren’t nearly as long. Since aspens are prone to disease and insect damage, they’re already fragile, and Denver’s soil and climate aren’t ideal for them to grow and thrive. Because of this, most aspen trees in Denver only live up to 25 years before they succumb to disease, insect infestation, or poor health.

How to Grow Aspen Trees in Denver

Although Denver is not the perfect location for aspen trees to grow, it’s still possible to have a healthy aspen in your landscape. In order to successfully grow this particular tree, you’ll have provide extra TLC, and you’ll have to amend your soil. When choosing the right spot to plant your aspen tree, make sure the soil is slightly acidic and well-drained. You may need to add gravel and the proper nutrients in order to achieve the right pH level. 

It’s also important to think about the root structure before planting your aspen. Will it have room to grow and spread out, without damaging the foundation of your home or other structures? Make sure you give your tree plenty of room to spread out, or else you’ll end up with problems several years down the road.

If you’d like to learn more about aspen trees, or if you’d like to know what trees to plant in Denver, we’d be happy to help. Contact us today.

Here in Denver, snow and ice are are winter staples, and most trees have learned to adapt to these harsh conditions. Even so, trees can be severely damaged by the weight of compacted snow and thick layers of ice, leading to dangerous conditions for the tree’s health — and your own. Let’s look at some things you can do in order to save your damaged tree after a snow storm.

What are the Signs of Snow and Ice Damage?

Some common signs that your tree has undergone damage from snow or ice include:

• Bowed branches, reaching toward the ground
• Snapped branches on the ground
• Broken branches hanging in the tree
• Torn pieces of bark or shattered branches
• The tree is leaning abnormally

Assess the Damage to Your Tree

Before assessing your tree, make sure the conditions are safe enough for you to approach the area. From a distance, observe your tree and look for signs of bowing branches or a leaning tree. Look for downed power lines or broken branches that are leaning on power lines above. If you can safely approach the tree, and it’s small enough, you may be able to save it yourself. If, on the other hand, your tree is very tall, or if there are large, broken branches on the ground, it’s best to call a professional. Branches are heavy, and an arborist will have the equipment and knowledge to safely care for your injured tree.

Carefully Remove Snow From the Tree

If your tree is small, and if you feel comfortable approaching it safely, you can begin to remove snow from its branches. Use a broom or other object to carefully sweep snow off the tree, effectively removing excess weight from its branches. If the snow is compacted or has begun to melt, you can use a shovel to knock the snow off.  Use upward sweeping motions and take care not to break or injure branches in the process.

Remove Broken Branches 

Broken limbs that are small need to be pruned at the point where they join larger branches. This will lessen the chances that your tree can become sick from bacteria entering its wounds. To prune small branches, it’s important to make cuts in the correct places. You’ll need to make a partial cut on the bottom of the branch, several inches from where it meets the trunk. Then, make another cut on top of the branch, but several inches away. That way, when it falls, the branch will fall easily. Finally, make a cut near the branch collar, where it joins the trunk. 

Large branches that are broken will need to be pruned as well. In most cases, it’s best to call in the pros. They’ve got the tools and expertise to safely prune your tree, while ensuring that it will heal properly where cuts have been made.

Bracing and Staking Your Tree

If your tree is young and leaning significantly, it may be necessary to provide support so it will continue to grow vertically. To do this, use a mallet to drive two or three stakes into the ground around the outer perimeter of the tree’s root ball. Then, push the tree upright by carefully adding even pressure to its trunk. Use special straps to attach the stakes to the tree, and make sure the tree has enough slack to sway, but is thoroughly supported. 

A young, leaning tree may require bracing and staking for up to a year in order to ensure that it grows correctly.

Spring Fertilization 

As always, a healthy tree is most likely to weather storms with ease while avoiding disease and infestation. You can encourage your tree to stay healthy and strong by fertilizing it each spring.

If you’ve got questions about how to care for your trees after a snow storm, or if you’d like tips on how to keep it healthy, we’d be happy to help. Contact us at American Arbor Care today.

What is Ascochyta leaf blight?

Ascochyta leaf blight is very common disease that affects Kentucky bluegrass. It is also problematic for tall fescue and perennial ryegrass, among others, but it seems to affect Kentucky bluegrass most often. It can develop overnight, leaving your lawn looking drought-stressed and dead. Although it may seem intimidating, Ascochyta leaf blight isn’t as detrimental as it looks. Symptoms may begin to appear throughout the spring and early summer, and it’s especially common when rainy spring conditions lead to hot, drought-like summers.

What causes it?

Ascochyta leaf blight is caused by Ascomycete fungi. Although its development isn’t completely understood, it thrives in wet conditions in the springtime. Most often, Ascochyta leaf blight develops when soil conditions have not been properly maintained, and moisture levels have fluctuated greatly between very wet and drought-like periods.

Once it’s present in your lawn, you can exacerbate the problem by mowing frequently, especially with dull blades. This causes wounds to develop in your grass, allowing the disease to spread.

What does it look like?

Oftentimes, Ascochyta leaf blight resembles drought stress, leaving large, uniform patches of straw-like grass. It may look like your lawn is dead, but there may be healthy green blades of grass interspersed throughout. Ascochyta leaf blight can develop very quickly, beginning at the tips of each blade, and moving downward. Luckily, the roots are not usually affected.

What types of grass does it impact?

Most often, Ascochyta leaf blight affects Kentucky bluegrass, but it’s been known to be present in other types of grass, including tall fescue and perennial ryegrass. Since Kentucky bluegrass is prevalent throughout Colorado, Ascochyta leaf blight has become quite a nuisance.

Can it kill your lawn?

Although it may look like your lawn is quickly dying, Ascochyta leaf blight does not cause any permanent damage. This fungus affects the leaves of the plant, and it typically leaves the roots unaffected. While it’s not harmful, leaf blight can make your lawn look awful, and it can quickly ruin all the hard work you put into landscaping. Luckily, there are things you can do to prevent and manage Ascochyta leaf blight, so your lawn will be lush and green again in no time.

How can you get rid of it?

The best way to manage Ascochyta leaf blight is by preventing its growth in the first place. To do this, water your lawn consistently and deeply. Aim for one to 12 – 20 minutes of deep watering per zone every other day to maintain steady moisture and keep leaf blight at bay. Avoid watering at night to prevent the spread of the disease. It’s also important to mow your lawn when the grass is dry. Avoid early mornings and evenings when dew is present since the water will spread the fungi throughout your lawn. Aim for your lawn to be around 3 to 3 ½ inches in length, and try to mow about 1/3 off the top each time.

If your lawn does show symptoms of blight, simply encourage it to grow quickly. Since there is no fungicide available for Ascochyta leaf blight, your best bet is to encourage healthy growth so the affected grass grows out. The best way to do this is by fertilizing frequently and aerating your lawn in the fall to keep it healthy. 

If you’d like to learn more about how to keep your lawn healthy, strong, and fungi-free, contact us. Our experts at American Arbor Care are happy to help.