Tree and Shrub Summer Update

Japanese Beetles

If you have Crepe Myrtles, Cherry Trees, Purple Plum Trees or River Birches, you are probably seeing quite a few Japanese Beetles. Adult Japanese Beetles are 3/8-inch long metallic green beetles with copper-brown wing covers. Adults emerge from the ground and begin feeding on plants in June. Individual beetles live about 30-45 days. Activity is concentrated over a four to six week period, beginning in July, after which the beetles gradually die. Adults feed on the upper surface of foliage, chewing out tissue between leaf veins. This gives the leaf a characteristic skeletonized appearance. They tend to do little feeding on thick, tough leaves. The current applications in our Tree & Shrub Program are designed to minimize the damage caused by the beetles. Call for a free estimate if you would like more information on our Tree & Shrub Program.

IMPORTANT NOTE ABOUT JAPANESE BEETLE CONTROL: There are no repellants for Japanese Beetles. Our goal is to minimize the damage caused during the summer with our program. If you have plant material on your landscape that is favored by the beetles, you will see damage. The contact aspects of our products will control any beetles that are on your plants when we are there, and our products also have a residual that remains with your plants for any beetles that come to feed later. The beetles will take a few bites, and they will either leave or die. But if you have 500 beetles come visit you and  they all take 3 or 4 bites, you can still expect a significant number of holes on your leaves even with our control measures.

 

Are Your Azalea's Leaves Turning Yellow?
Meet the Azalea Lacebug

Many people mistake the yellow or white discoloration commonly seen on azaleas this time of year as drought stress, fungus, or some type of root problem. Most of the time the cause of this discoloration is the LACEBUG. The damage caused by lacebugs to azaleas can severely reduce bloom potential. Azaleas are mainly planted in landscapes because of the brilliant colors exhibited when they bloom in the spring. The plants are rather boring otherwise. For this reason it makes sense to minimize the damage caused by lacebugs in order to insure the best blooming and color possible in the spring.

Adult lacebugs are 1/8” to 3/16” long with light brown bodies and clear, ornate lacy wings. Nymphs are darker in color and wingless. Lacebugs are piercing/sucking insects; their mouthparts are like small needles. They insert the needle into the soft flesh of the azalea leaves and suck out the water and nutrients. Lacebug feeding results in yellow or white spotting of the upper sides of an azalea’s leaves. Dark brown spots appear on the bottom of the leaves from the insect’s excrement and discarded body casings.

Lacebug eggs hatch in the early spring, and populations peak in the mid to late summer. This is when the damage to azalea leaves is most evident.

Repeated treatments are needed in order to properly control lacebugs. We begin our control process by applying horticultural oil in the early spring to control the over-wintering eggs. Later in the spring and summer we apply different contact and systemic control products to the undersides of azalea leaves in order to minimize the damage.

Since azaleas are broadleaf evergreens, they do not lose all their leaves each season. Thus, the damage caused by lacebugs will be evident in future seasons. Our Tree & Shrub Program is designed to help damaged azaleas recover from this damage with our season ending deep-root fertilization. This fertilizer is injected in the ground around the azaleas’ root zones. This slow release fertilizer will help the plants replace the nutrients lost and it helps to maximize the spring blooming potential of the plants.

 

 

Watering Your Trees and Shrubs

Blanket watering your plant beds like you water your lawn leads to wasting water and money. During the summer it is a much better idea to selectively water your plants, as they need it. Plants only need watering in addition to normal rainfall when they start showing signs of drought stress. This will be evident by wilting leaves and loss of color in a particular plant. Unfortunately these symptoms are also signs of many other problems-including TOO MUCH water around the roots. So you should always physically inspect the area around the root zone before watering to see if the root zone is dry. If it is dry, water the plant. If it is soaked, you will need to find a way to keep some of the water away from the roots.

Most of us don’t have time to stand in the yard and hand water every plant on the landscape. For that reason, we suggest using methods of watering that place the water as needed around the individual plants needing water. A soaker hose allows water to slowly soak out around the base of a plant. You can attach a soaker hose to the end of your regular hose and thread the soaker hose around several plants at a time. Another type of selective watering is the drip irrigation line. This is a plastic line that has outlets that drip water slowly around the base of a plant.

Plants needing water should be watered at the rate of 1 gallon per foot. Flowerbed areas or ground cover areas should be watered at a rate of 50 gallons of water per 100 square feet. You should take the time to calculate how long it takes to apply this much water depending on your water pressure and the type of irrigation method you are using. Capturing the water in a container and timing how long it takes to apply the appropriate amount of water can accomplish this. Keep in mind that you need to water slowly enough to avoid runoff.

Tree & Shrub FAQ: Q: Why do I still have insects eating my trees and shrubs if I am a Tree & Shrub Program customer? A: This is a commonly asked question. This simple truth is we do not have repellants for the insects that feed on your plants. There is no “Deep Woods Off” for Japanese Beetles. Our products are designed to minimize the damage caused by sucking or chewing insects on your ornamental trees and shrubs. In most cases, the insects need to feed on the plants in order for the products to control them. Minimization of damage from these insects is our goal.