Unwanted Pest #2: Asian Longhorned Beetle

We’re almost to the end of our series on the Most Unwanted Garden Pests. This is villain #2: The Asian Longhorned Beetle (ALB).

The ALB (Anoplophora glabripennis) doesn’t live in our area (Westchester, Bergen and Fairfield counties) – yet. And hopefully, it won’t. Intensive eradication efforts are ongoing in New  York City, Long Island, Massachusetts, Union and Middlesex counties in New Jersey and Ohio, the areas where ALB is currently residing. The USDA is taking an aggressive approach to this mission – any tree infested by ALB is cut down and burned.

Why is the ALB so despised? Because of the deadly outcome of an ALB infestation and the extensiveness of their diet.  In our area, we’ve had several species of trees virtually eradicated by insects or disease over the last century: the American Chestnut by chestnut blight, the American Elm from Dutch elm disease, and – currently – several species of ash trees from the Emerald Ash Borer. But the Asian Longhorned Beetle has the potential to decimate several widely growing tree genera in our area, including maple, birch and sycamore. In addition to the loss of these beautiful trees, the economic impact on our hardwood forests would be immense.

The story of the ALB’s infiltration into the U.S. sounds like a spy movie. Someone notices a suspicious looking insect. They call a government agency. The insect is identified as a stowaway assassin from China. Soon after, the Feds swoop in and destroy the insects along with any possible hiding place. They search the neighborhood looking for more insects and any possible shelters – and in a slash and burn frenzy, cut down any trees that could harbor these terrorists.

Yet this dramatic response seems to be yielding results. The ALB appears to have been eliminated in the Chicago area, and it looks like New York and New Jersey may soon follow. Massachusetts is still battling hard and finding new ALB hideouts.

The USDA’s Animal and Plant Health Inspection Service (APHIS) actually acts like Homeland Security for invasive pests. They have intercepted ALB in warehouses in California, Florida, Illinois, Indiana, Massachusetts, Michigan, North Carolina, New Jersey, New York, Ohio, Pennsylvania, South Carolina, Texas, Washington and Wisconsin.  And their Canadian counterparts have intercepted the ALB in several provinces there. 

Asian Longhorned Beetle Exit Holes
Source: Kenneth R. Law, USDA APHIS PPQ, Bugwood.org 

One thing that works against the ALB is its size and striking markings. The beetles are over an inch long and colored like a Mardi Gras mask. In several cases, an ALB was identified when someone saw it and said, “What IS that thing?”  When a tree is infested with ALB, the exit holes can make it look like it’s been strafed with a machine gun.

Right now, the best chance we have of defeating the ALB is public awareness. So if you see a large, gaudy beetle, call for backup! This USDA site will give you more information: http://beetlebusters.info/ (It’s worth visiting just to see their CGI beetle!)

Unwanted Pest #3: Hemlock Wooly Adelgid

If you have hemlocks in your yard, you probably already know of the Hemlock Woody Adelgid (HWA). This tiny aphid-like insect has been attacking and killing hemlocks throughout the eastern United States.  The devastation it causes makes it #3 in our countdown of Most Unwanted Landscape Pests.

Both the Carolina Hemlock and the Eastern Hemlock are victimized by the Hemlock Wooly Adelgid. This insect doesn’t restrict itself to weak or stressed trees – healthy trees can be infested as well. Although a tree can survive an attack from the HWA, continued infestation is deadly, robbing the tree of the needles necessary for survival.

There are no preventive measures for HWA; hemlocks should be inspected frequently for signs of infestation. You aren't likely to see the adelgids:  they are so tiny they are almost imperceptible. But the signs of their presence are unmistakable: little dots of cotton appear along the base of the needles where they meet the wood. These cottony blobs are protecting the HWA eggs. When the crawlers emerge, they will latch on at the base of a needle and start draining the hemlock of its vital fluids. Obviously, a single adelgid doesn’t drink much; but as the population grows, the cottony balls extend along every branch, harboring millions of thirsty adelgids. Within a few years of infestation, the hemlock is usually dead. Some of our beautiful, native hemlock forests have disappeared because of this foreign invader.

Hemlock with wooly adelgids.
Source: John A. Weidhass, Virginia Polytechnic Institute
and State University, Bugwood.org

Fortunately, this is an insect that we can successfully battle. Both foliar sprays and systemic controls are available that can give us the upper hand against these insects. There are several factors that should be considered in order to determine the best course of treatment, such as the size of the tree, the extent of infestation, soil and weather conditions and proximity to streams or ponds. Your Almstead arborist will evaluate how these factors impact your hemlock and propose a method for combating these evil adelgids.

In the future, there may be biological controls for HWA. Currently, experiments with predatory insects and fungi look promising, especially for forests where the cost of treating individual trees is impractical. For now, careful monitoring and early action are the best safeguards against Hemlock Woody Adelgid.

The Secrets of Compost Tea

Michael Almstead, August 9, 2012. 

The Compost Tea Workshop was held on the beautiful 

campus of Rye Country Day School.

Last month, Almstead had the opportunity to conduct a workshop on Compost Tea and Air Spading for the Northeast Organic Farming Association (NOFA). Arborist Dan Dalton and I, along with compost tea brewing specialist Russell Wagner and lawn technician Marc San Phillipo and several other Almstead professionals, really enjoyed being able to share our knowledge and experience with others interested in organic tree and plant care.

The workshop was intensive. We covered both the science behind Compost Tea brewing and the practical issues and hurdles to creating a brewing business. I’ve been involved in Almstead’s evolution into organic care from the beginning and believe that products like compost tea are win-win: healthier for the lawns and trees as well as the environment, friendlier to consumers, and safer for everyone.

Continual aeration is a necessity for compost tea.

Brewing high-quality compost tea is an involved, scientific and careful process. Compost tea is NOT a slurry of compost and water. It must be carefully balanced to meet the nutritional requirements of the plants it’s meant for.  It contains living organisms that have to be kept alive through constant aeration – both while the tea is brewing and in the truck delivering it.

Russell Wagner microscopically checks our Compost Tea

 for the proper microorganisms and fungi.

We have a mini science lab in our Compost Tea brewing facility, where we examine everything going into the tea. We want it loaded with beneficial organisms, both bacteria and fungi; we add them, and make sure they are live and happy (and in the proper proportions) in the tea before we apply it. We also make sure that no damaging organisms are sneaking into our mixture.  This quality control is vital to brewing compost tea – without it, you’d  just be delivering a truckload of dirty water.

We have a rather substantial Compost Tea brewing operation here at Almstead. Compost tea is an organic way of adding nutrients and microorganisms to the soil – sort of a jump-start for soil to rejuvenate itself, making it more attractive for worms and other beneficial organisms, and keeping the process of soil development going. And it dramatically cuts down the use of chemicals, a plus for both for the environment and for people who are exposed to their lawns.

Dan Dalton describes the nutrient cycle.

Dan Dalton taught the segment on soil properties. He emphasized the necessity of understanding the chemical, physical and biological elements of soil in order to create a compost tea – sometimes augmented by other organic amendments – that facilitates the right soil profile. This goes way beyond simple pH – it includes factors such as adjusting the particle size of soil components and encouraging symbiotic fungi that help keep damaging organisms away from tree roots.

We create different teas for lawns and for trees because of their varying requirements. Lawns need a higher ratio of bacteria, while trees require more fungi. For large locations (like a college campus or business park) we can create a Compost Tea based on soil testing. Sometimes we add specialized ingredients like nematodes or mycorrhizal fungi to meet their specific needs.  We talked in general about recipes for compost teas – but the formulae that Almstead has carefully developed for our clients remains a closely-guarded company secret.

The participants examine fibrous roots exposed
by air spading.

Our NOFA presentation also included a demonstration of air spading. Air spading (using compressed air to loosen soil around tree roots) is a wonderful tool of organic tree care. There are several methods we can choose from, depending upon the results desired. Essentially, by using the air spade, we can loosen and/or remove compacted soil. We fill in with looser soil and amendments, allowing the tree roots to “breathe,” encouraging them to grow and giving them easier access to the nutrients and water in the soil.

Russell performed air spading on one of the Rye Country Day School campus trees. Since fibrous roots are concentrated in the top 8” of soil, compaction can deprive a tree of both oxygen and nutrients. First , he excavated the critical root zone around the trunk, easing soil compaction and allowing examination of the roots for signs of girdling or disease; then he air spaded out radially from the trunk (like slicing a pie).  These slices were filled with compost and other soil amendments to provide the roots with easy access to oxygen, water and nutrients.  

Marc San Phillipo demonstrates soil injection 

of compost tea into the root zone.

Mark San Phillipo also demonstrated the soil injection of compost tea into the root zone. Compost tea can also be used as a soil drench.

By the end of the day, the workshop participants seemed to leave with a new appreciation for these important tools in organic plant care.

-             --- Michael Almstead, Vice President & Arborist

Unwanted Pest #4: Scale

Our reverse countdown continues. #4 in our list of the most Unwanted Landscape Pests is Scale.

Scales are tiny insects, less than ¼”, that do almost nothing – except suck the life out of plants. There are 7,000 different types of scale insects, broadly divided into armored and soft.

Scales live boring lives. A female insect attaches herself to a leaf or shoot and begins to feed. She lays eggs beneath herself (some scale insects mate while others can reproduce without outside help) and provides shelter while they develop. “Crawlers” emerge and start to seek out their own locations. After a few days their mobility is over: they hook onto a plant and begin sucking -- forever.

Woolly Pine Scale
Source:  Terry S. Price, Georgia Forestry
Commission, Bugwood.org

  Although immobile, scales have protection. Armored scales create a hard protective covering, basically a shell. In fact, some scales are referred to as oyster shell, while others look like small pearls. Soft scales are covered in a waxy coating; they often appear as fuzzy white dots of fluff on a plant. Most release fluids as they suck; this sticky “honeydew” can cause even more problems by attracting other insects or mold – and dripping on anything below.

Scales are so tiny that they are rarely noticed until the population has increased to troublesome size. But, en masse, they can harm or even kill plants – even trees. Their lack of mobility causes them to feed in ever-increasing numbers on their host plant.

Scale’s armored or waxy coating makes them difficult to kill. They are only vulnerable to insecticide sprays during their brief crawling stage. Thorough drenching in horticultural oil or insecticidal soap can also combat scale. Finally, systemic treatments are available that cause the tree to repel the feeding insects.

Magnolia Scale
Source:  Brian Kunkel, University of Delaware, Bugwood.org

There is no single treatment for scale insects – nor do all scale insects need to be removed. Almstead arborists and technicians examine every tree to determine the most appropriate treatment, based on factors including the type of scale, the stage of development, and the size of the tree.