Pest Control


The mistakes of years ago have caused most homeowners to recognize how important it is to be aware of safe, environmental control measures.  The correct product and method of application not only delivers good results, but leaves no damaging environmental footprint. 

Organic Foliar applications, Soil Injections, Basal Trunk Drenches, Trunk Injections, Baits, and traps are all considerations when determining how to control a particular pest infestation.  Customer concerns and preferences are all part of the Arbortech Advantage.

Pests such as Ticks, which can cause serious harm to the human populations as well as our pets, need treatments applied with the most conscientious concerns being addressed.

Cedar Oil applications will control both active Tick populations and their eggs.


What is Hemlock Woolly Adelgid?

Adelges tsugae 3225077

Hemlock Woolly Adelgid is an aphid type insect pest that is so small it can’t be easily seen.  A hand lens will reveal the pest itself but the white cottony covering they develop to cover and protect themselves is quite noticeable.  At first glance it resembles the tips of a q-tip swab.  These pests feed at the base of the Hemlock needles nearest the stem.  This pest feeds on sap, retarding nutrient flow to the needles.  This disruption causes the tree to eventually starve, causing needle drop/defoliation and leaving an open door for other stress factors, both insect and disease and weather conditions cause additional decline.

How much damage can HWA do if left unchecked?

Hemlock Woolly Adelgids will devastate your Hemlock trees causing their complete failure within a few years.  HWA is of epidemic proportions in the Northeast at present and has destroyed thousands of acres of Hemlocks.

How can Hemlock Woolly Adelgids be controlled?

Control measures for HWA are determined by several factors:  tree health, age of tree, location and number of trees involved are all considerations.  Treatments can include foliar sprays, trunk injections, basal trunk drenches, and soil injections.  If applied properly, all have proven to be effective.

What else should I be aware of?

Hemlocks are a specie of tree that stores their nutrients in their needles over the dormant season.  Trimming, shaping, pruning (removal of the needles) on this specie will cause the tree to starve over the winter and spring growing season.  Time any cutting of these trees appropriately. 

Never feed /invigorate Hemlocks with nitrogen based fertilizers, as Hemlock Woolly Adelgid populations will explode, as Adelgids love to feed on the nitrogen.


Ticks in our area

Adult deer tick

Ticks are biological blood suckers, vampires of sorts, that require a human or animal host to survive.  Ticks are not insects, but arthropods, which are related to mites, spiders and scorpions.

There are about 12 species of ticks that are of health concerns in the United States.

Our Northeastern region is a haven for Black Legged Tick or Deer Tick, Lone Star Tick, Rabbit Tick, American Dog Tick, Woodchuck Tick, Brown Dog Tick and Bat Tick.

All of these ticks are of medical concern and control measures should be considered.  Ticks are parasitic vectors that feed on there animal/human host and can be held responsible for Zoonoses, a disease caused by a pathogen that is maintained in vertebrate animals that can be transmitted to humans or domestic animals by a vector or thru other means.

How dangerous are Ticks?

You probably know or have heard of someone who has contracted a disease that is associated with Ticks.  Babesiosis, Colorado Tick Fever, Ehrlishiosis, Lyme Disease, Rocky Mountain Fever, Tularemia are just a few of these diseases.  All of these are serious health risks you never want to battle with.

How can I prevent and control Tick problems?

If you know you are going to be in a Tick infested area, wear light colored clothing with your socks tucked in.

  • Use Deet or Permethrin based repellants.
  • Keep your properties debris free when possible.
  • Inspect yourselves, children, and pets for hitch hikers.
  • Keep grass mowed.
  • Manage pet activity, keeping pests out of wooded areas.
  • Use chemical controls in combination with cultural, mechanical and physical controls to achieve results.
  • Traps for rodents, weed management and barriers to keep birds and insects out, are a few examples.
  • Have a professional monitor and set up a good Tick Control program.


What is a Gypsy Moth?

Lymantria dispar MHNT Chenille

The Caterpillar stage of a Gypsy Moth when young is about ¼ inch long and are usually black in color with blue and red dots.  As they eat leaf tissue and grow they can grow 2 – 3 inches in length and develop colorful spots.  Their hairy bodies actually inhibit birds from eating them.

When is the best time to control them and how?

The most appropriate control measures are when the Gypsy Moth are in larvae stage, usually in May thru late June.  After the larva transform into moth you can get some control using pheromone traps that catch the male moths that fly.  Females remain on trees, woodpiles and places with some type of cover and lay their eggs for next year.

What trees do Gypsy Moth eat?

Almost any green tree can be attacked by Gypsy Moth.  They especially like Oaks, Maples, Birch, Apple, Willow, Elm and even conifers/evergreens, like Spruce, Pines, Hemlocks, etc.

How to control Gypsy Moth?

There are several methods of control available, each of which should be specific to particular trees in question.  Specific foliar sprays, trunk injections are most affective when in the caterpillar stage.  Pheromone traps are an affective tool when pests are in the moth stage, catching the males to stop fertilization of females for next years’ infestation.

Also calculate Growing Degree Days.

How do I know I have a Gypsy Moth problem?

In spring Gypsy Moth caterpillars start feeding and eat holes in leaves, digest the leaf tissue and pass it thru their systems, leaving small brownish droppings on everything below.  This defecation is called Frass and can make quite a mess.  After feeding for only a short period, tree defoliation becomes very noticeable.  After the feeding cycle of this pest is over, the larvae morph into a moth, tan in color and can be seen flying all around infested areas.  Males are the flyers and females are most often viewed on tree trunks and limbs, laying their eggs.

What can be done to help trees if attacked by Gypsy Moth?

Gypsy Moth caterpillars can devour a tree in foliage completely in one spring season.  The loss of foliage puts trees and shrubs in jeopardy of other pests and disease problems due to a loss of vigor. Spraying and trunk injection treatments are very effective in controlling Gypsy Moths.

Tree Invigoration is highly recommended to compensate for this damage.  Invigoration products and methods are consideration and should be addressed on the specific trees’ merit. 


What is a Mite?

Tetranychus urticae with silk threads

Mites are not insect pests, they belong to the Arachnid Class, the same as spiders and ticks.  Most mites cannot be seen with the naked eye.  A good indicator of mite activity is the presence of silky-like webbing.  Stippling or color change in plants is also a sign mites may be active.

Adult mites are much larger than their offspring and can be seen on occasion with the naked eye.  Mites can be found on both conifers and deciduous trees.  Mites damage trees by sucking cell contents from foliage.  They will do their damage primarily during hot weather.  However there are mites that feed in the cooler months also.

Why do my plants get Mites?

Mites are pests of opportunity.  Such stresses as extreme heat, water stress or drought, dusty locations along roads and the use of certain broad spectrum pesticides that kill mite predators are a few reasons why mite populations can reach unacceptable tolerance levels.

How can Mites be controlled?


Plant hydration is important in controlling mite populations.
Keep plants irrigated.

Use only mite specific chemical controls to avoid enhancing mite populations.

A good arborist will be aware of this information.  Foliar sprays and trunk injections work well if populations are monitored and addressed in a timely fashion.

(Pissodes strobi)

What is a White Pine Weevil?


Considered the most damaging insect of White Pines, this pest infests the terminal leader of Eastern White Pines, Austrian Pines, Jack Pines, Pitch Pines, Red and Scots Pines.  It also attacks Serbian, Norway and Colorado Blue Spruce.  The telltale wilted dead center lead on host trees is a sure sign this pest is at work.  Usually you can notice resin soaked droplets on the terminal leader, as it is the result of feeding and cutting of egg laying sites. The damage caused by this pest, affects both health, shape and aesthetic appearance of the host trees.

How can White Pine Weevil be controlled?


Timing is important when treating White Pine Weevil.  Arbortech has found that in most cases one spray application of a registered pesticide designed specifically to control this pest, works well.  Removal of affected tissue is also a good control measure that we can provide. 


What is an Emerald Ash Borer?

Agrilus planipennis 001

Emerald Ash Borer, also known as EAB, is as its name describes, a boring insect which attacks and kills Ash trees.  It was discovered in the US around the early 1990’s and came from Asia.  When in the beetle stage of its life, it deposits its eggs under branches and along the trunks of trees, in cracks and crevices which are suitable.  Its color is also descriptive in its name as it displays a metallic emerald green brilliance.  Once it invades the inner cambial layers as a borer, it creates destructive tunnels in the water and nutrient carrying tissue of the tree, thus cutting off the flow of these life sustaining materials between the roots and the leaves.  Once the infestation occurs, the tree will usually die within two to three years time.

How can I tell if my tree has EAB?

The adult beetles create small “D” shaped exit holes in the bark.  A noticeable thinning canopy can appear.  Dead and defoliating leaves in the crown will be visual.  Bark splitting can occur and a noticeable increase in woodpecker activity caused by birds feeding on beetle larvae. 

What can I do to save my Ash tree?

Preventative treatments are the best methods of protection.   Once trees are infested, treatments may not be as successful.  Treatments may include Trunk Injections, Soil Drenches, Basal Trunk Wash, as well as physiological directions such as fertilization, aeration and watering.  Don’t allow this invasive pest to devastate your Ash tree.

Call Arbortech for a free inspection and put together a practical preventive program.  If you wait too long you can probably kiss your Ash good-bye.


What is a Lacebug?


Lacebug is a very small insect pest, which has body parts that resemble lace, thus the name.  Lacebugs are usually host specific.  Lacebugs pierce the undersides of leaves and needles and feed by sucking the sap from the foliage.  Most Lacebugs in our area have one or two generations per year, but some species have many more generations. 

Lacebug feeding can cause severe damage to trees and shrubs. 

What are the signs of a Lacebug infestation?

Azalea lace bug  rhodie 1

Trees and shrubs that are under attack from Lacebugs usually exhibit leaves that are bronzed or have a silvery appearance.  Most infestations leave frass, spots, shedded skins and excrement on the undersides of foliage that help to reveal their presence.

Although Lacebugs feed on the undersides of leaves, the damage is most apparent on the upper leaf surface.  Lacebug is a common pest on evergreens, Azaleas, Rhododendrons and Andromeda, but will also attack a wide range of other trees and shrubs.

How can Lacebugs be controlled?

Early spring inspections will reveal the presence of overwintering Lacebugs along with their eggs and newly hatched nymphs.  Treatments should not be delayed as early damage stays with the plant for the whole growing season.  Affective treatments that may be considered range from horticultural oil and insecticidal soap sprays, to Trunk Injections and Drenches and long residual spray chemicals (Imidicloprid)   Minor infestations can even be controlled by strong stream water washing.

Arbortech can provide a program to control your Lacebug problem that is best suited for you specific infestation.

(Malacosoma americanum)

What is Eastern Tent Caterpillar?

TentCaterpillarTent 040508

A native pest of North America, the Eastern Tent Caterpillar can be found destroying your fruiting and flowering trees in late spring and early summer.  This pest will also attack Hawthorne, Maple, Wild Cherry, Purple Plum and others.  Tent Caterpillar over- winter as egg masses that surround smaller branches.  Each egg mass can contain anywhere from 100 to 400 eggs.  The Caterpillars hatch and form nasty silk-webbed tents in a crotch or multiple crotches of host trees.

How will I know if I have Eastern Tent Caterpillar?

The most revealing visual is the silky nest or tent, which is very difficult to break apart.  Caterpillars usually grow to 2 l/2 inches long and are hairy, black in color with a white stripe in middle of back and shows brown and yellow lines along the sides.  Its colors are accented by a row of blue spots on the sides.  This pest is often mistaken for Forest Tent Caterpillar or even Gypsy Moth. 

How can Tent Caterpillar be controlled?

Remove and destroy the egg masses if detected early on.  Small tents can be removed by hand and destroyed.  If you are not accustomed to handling hairy worms or egg masses, Arbortech has a variety of controls, which are all specific to the life cycle of this pest.

Chemical applications, egg mass removal and tent removal are all practiced.


What is an Aphid?

Acyrthosiphon pisum (pea aphid)-PLoS

Aphids are small insects that can be found on almost any plant.  They can be quite damaging to trees and shrubs by sucking out essential fluids.  Aphid populations can range from insignificant to overbearing. 

What do Aphids look like?

Most Aphids have soft bodies, long legs antennae and are red, black brown or green in color.  Many Aphids develop wooly or waxy cottony coverings or coatings to help protect them.  In some cases adults are wingless, but many species occur as winged-pests.

How damaging can Aphids be?

Small numbers of Aphids do little damage, but when large populations develop they can be very devastating to trees and shrubs.  Aphid feeding can result in stunted growth, curled foliage, discolored leaves and may lead to gall formations.  Heavy Aphid feeding can result in a sticky exudate to be produced. (honey dew)  Some Aphids can affect plants with toxins and transmit viruses from plant to plant.

How can I control Aphids?

Start by monitoring you plants often to see if populations are starting to develop or cause damage.  If you find only a light infestation, a simple water wash can be affective. If populations are high and spreading, you may need a chemical control. 

Arbortech has a variety of controls available ranging from cultural implementation to natural alternatives, as well as chemical controls that can be applied via Soil Injections, Trunk Washes and Trunk Injections, including Foliar Sprays of both long lasting systemic and organic types.

(Camponotus pennsylvanicus)

What is a Carpenter Ant?

Carpenter ant Tanzania crop

Normally Carpenter Ants nest in tree cavities, logs, rotted stumps and seldom tunnel into sound wood, but will still eat moist rotted wood, such as that found in trees with rotted areas, where healing and good callus tissue formation has not occurred.

Carpenter Ants are usually more noticeable than other species because of their black color and larger size.  This pest can affect the structural strength of trees and should be addressed as soon as possible, if detected.  Carpenter Ants have voracious appetites and tree infestation can easily lead to home infestation if left unchecked.

Arbortech can provide the best treatment for your Carpenter ant infested tree, which can include baits, dust or chemical spray applications.  We use products that are non-toxic to mammals and give excellent control.  We can also assist in removal of debris sites that are havens for Carpenter Ant development.

(Otiorhynchus sukatus)

What is Black Vine Weevil?

Otiorhynchus sulcatus 23-8-2007 20-10-41

Black Vine Weevil is one of the most damaging pests found in nurseries and established landscapes.  It is considered the most destructive pest of Rhododendron.  It also loves to eat Taxus, Euyonemous and Japanese Holly and is found on at least 100 other species.

This pest over winters in the soil, emerges in late May thru June and does its feeding at night.  Black Vine Weevil hides during daylight hours in mulch, leaf litter and on branches with shady foliage.  This pest feeds primarily on roots of the host plant and will also attack the stems and foliage.

Black Vine Weevil2

How will I know if my plants have Black Vine Weevil?

Most Black Vine Weevil infestations are first detected by the visual observance of marginal leaf notching.  Nursery plants should be closely inspected by a professional before planting.  One method of detection is to place boards or burlap on the mulch or soil area around the base of the plant.  During mid-day, lift the board or burlap slowly to reveal the presence of the adult Black Vine Weevil.

How can you control Black Vine Weevil?

Monitoring is the first direction to determine if a problem exists.  Arbortech can provide this service as well as apply any chemical control measures that are needed.  Foliar Sprays of environmentally friendly chemicals can be used or Soil Drenches, which will give a longer residual.

JAPANESE BEETLE (Popillia Japonica)


What is a Japanese Beetle?

Japanese Beetle is a very destructive pest of approximately 200 plant species in this country.  A native of Japan, this beetle was discovered in the U.S. in 1916, in a nursery in Riverton, N.J.  It is believed it found its way here, as a stowaway in a shipment of iris bulbs.

How will I know if I have Japanese Beetle?

Japanese Beetle are big time heavy eaters that love to devour the leaf tissue between the veins of leaves.  The visual pattern that they are eating leaves is called skeletonizing.  You will almost surely see these pests as they are poor flyers and tend to bounce off obstacles in their way.  They are easy to spot as can be seen in the photo.  Although they eat many plant species, here’s a few they like around this neck of the woods:  Linden and Birch trees, Cherry, Plum, Apple, Pear and Arborvitae trees.  Maple, Hydrangea, Crabapple, Oak, Rhododendrons, Willow, Sassafras, Elm and Viburnim.  Oh yeah, they like it all!!

What can I do to control Japanese Beetle?


To start with, it’s probably best NOT to put out JB pheromone traps!  Although meant to monitor populations of JB, they tend to bring in so many its like blowing the lunch whistle.  During a  larval stage of their lifecycle, they are susceptible to a disease called Milky Spore caused by the bacterium known as Milky Spore (paenibacillius popilliae)

This Milky Spore is a biological control and is available in powder form, which is applied to lawn areas.  Standard applications take from one to five years to establish maximum protection.

Chemical spray applications are fast and work extremely well.  Environmentally friendly pesticides are all that’s needed.  

Arbortech has killed millions of these damaging pests.


What are Scale insects?

Scale Insects

Scales are sucking insects that damage trees and shrubs by sucking plant juices, thus causing a loss of plant vigor, die-back, chlorosis and can create honey-dew deposits that can develop into Sooty Mold.  (A fungal condition)

There are various types of Scale insects, Armored Scales, Soft Scales, Bark Scales, etc.

Scale insects attack a multitude of trees and shrubs, some of which can cause serious damage and death of that particular host plant.  The following is a list of some Scale specie and the plant specie they attack.

Azalea Bark Scale

Azaleas and Rhododendrons

Calico Scale

Magnolia, Maple, Dogwood, Honey Locust, Tulip tree, Sweet gum and ornamental fruit trees

Taxus Scale

Taxus, Hollies, Rhododendrons, Japanese Maple, Camellia and Mulberry

Cottony Cushion Scale

Maple, Fir, Boxwood, Cypress, Elm, Laurel, Locust, Pear, Oak and Willow

Euyonemous Scale

Boxwood, Euyonemous and Camellia

Cryptomeria Scale

Pine, Spruce, Hemlock, Taxus and Fir

Hemlock Scale

Mostly Hemlocks also Taxus, Spruce and Pine

Japanese Maple Scale

Japanese Maple, Dogwood, Lilac, Red Maple, Privot, Zelkova, RedBud, Cherry, Magnolia and Holly

Maskell Scale

Arborvitae, Leyland Cypress, Spruce, Yew and Cryptomeria

Obscure Scale

Pin Oak, White Oak, Dogwood, Hickory and Walnut

Oyster Shell Scale

Maple, RedBud, Hawthorne, Oak and many Prunus species

White Prunicola Scale

Prunus species, Magnolia, Rhododendron, Lilac and Boxwood

How can I resolve a Scale problem?

Arbortech has encountered all of the above Scale pests.  Treatments are best applied by first identifying the specie of both pest and plant involved.  Treatments may include Oil Sprays, Soil Injection or Drenches, Trunk Injection, or Foliar Spray applications of environmentally chemicals.

(Agrilus anxius)

What is a Bronze Birch Borer?


Bronze Birch Borer is an opportunistic pest that attacks White, Paper, Cut-Leaf, Weeping, Yellow and Gray Birch.  Its presence has also been found on Beech trees.

Drought stress has a major role in the development of Bronze Birch Borer outbreaks.  Bronze Birch Borer larvae over winter under the bark.  After molting into the pupae stage, adults chew thru the bark and emerge from “D” shaped holes.  Mating soon begins and females deposit eggs in cracks and crevices on trunks and stem areas.  Within a few days the eggs hatch and chew into the bark where feeding begins.  This feeding results in tunneling and the creation of criss-cross galleries which interfere with the flow of water and nutrients to the crown.

How can I tell if my trees have Bronze Birch Borer?

bronze birch borer damage

Close examination of tree trunks and branches can reveal bumps and ridges where tunneling has occurred.  The presence of “D” shaped holes can be seen if magnified.

In many cases trunks and branches may reveal a brown or orange stain.  Wilting and die-back of the crown is noticeable from a distance.

What can I do to control Bronze Birch Borer on my Birches?

Start by planting Birches in more shaded areas.  Resistant species such as River Birch and Monarch Birch are good choices.  Arbortech has several controls available to control this pest.  Trunk and Soil Injections work well.  Some soil applications can give long residuals and trees will be protected for as long as two years or more.  Arbortech also has fertilization and moisture management treatments available that will reduce Bronze Birch Borer attack and will keep your Birches healthy and looking good.

(Thyridopteryx ephemeraeformis)

What is a Bagworm?


Bagworm is an interesting pest.  Very clever at concealing its presence.

The Bagworm spins a cocoon while in its larvae and camouflages it with bits of foliage and needles from the tree on which it feeds.  Bagworms love to attack Arborvitae, Red Cedar, Spruce, Pine, Apple, Juniper, Birch, Black Locust, Elm, Maple, Oak, Poplar, Sycamore, Willow, Cypress and many more plant specie.  Bagworms have big appetites and will devour trees in a short time.  This is a serious pest if allowed to go un-checked.

How will I know if my trees have Bagworm?

In the fall the cocoons which were spun will turn brown and are much easier to spot.  In spring and summer foliage will become eaten and brown as feeding will become more advanced. 

How can Bagworm be controlled?

If infestations are minimal, hand picking the bags is very effective.  There are also a variety of environmentally chemicals that work well when applied as a Foliar spray.

Arbortech has a control program for Bagworm infestations that will be appropriate regarding the severity of the infestation.

(Neodiprion sertifer)

European Pine Sawfly

What is European Pine Sawfly?

This specie of Sawfly is the most common in our area.  It feeds on the needles of Pines and can cause aesthetic damage and decline of the plant.  This pest loves to attack Mugho Pine, Scots Pine, Red Pine, Jack Pine, White Pine, Austrian Pine and Pitch Pine, among many others.  Only one generation occurs per year.  Over-wintering eggs that were laid in slit like wounds by the females begin to hatch in late April thru mid-May.  Larvae start to feed on last years needles and at times the bark of new shoots. 

How will I know if my Pines have European Pine Sawfly?

sawfly damage

When young, this pest eats the surface of the needle causing the needle to appear dry and straw like.  Older larvae will devour the entire needle from tip to base.  Most plants are not completely defoliated as the larvae rarely attack the new foliage.

How can I get rid of European Pine Sawfly?

Host trees should be monitored in later April to mid-May.  If dry-straw like needles are found this affected area should be removed, as long as it does not affect the aesthetic appearance of the plant.  If more than a few plants are affected, clipping or pruning may not be efficient, as any larvae that remain can spread to other host plants.  There are several chemical spray applications that are environmentally friendly and work well.  Arbortech can control this problem very quickly.


What is a Bark Beetle?

Dendroctonus ponderosae

Bark Beetles can be one of the most damaging insects in North America.  This insect pest burrows into the bark of stressed, weakened or damaged trees.  These burrows or tunnels interfere with the flow of water and nutrients to the crown.  Drought stressed Pines are especially susceptible to Beetle attack, as well as Spruces and Firs.  There are many species of Bark Beetles.  Bark Beetles can also be found damaging other tree species such as Oak, Buckeye, Arborvitae, Cypress, Elm, Walnut, Junipers, Redwood and many other species.  Bark Beetles are also vectors (carriers of disease and fungal problems)  Pine Bark Beetles, Asian Long Horn Beetles and Ambrosia Beetles are just some of the most common pests found in our area. 

How will I know if I have a Bark Beetle problem?

The specie of tree attacked and location of damage on the tree help in identifying the Bark Beetles presence.  It usually takes a professional to provide this information.  The most obvious visual are holes in the outer bark, sawdust or frass around these holes which is usually present.  Some Beetles cause a distinct visual thinning of the crown, such as the Elm Bark Beetle, a vector of the Dutch Elm Disease. 

How can I control a Bark Beetle attack?

Cultural controls should always be considered when dealing with this problem.  Plant non-host trees in areas where Bark Beetles are common.  Reduce tree stress by invigoration and watering and proper removal of dead limbs and dead trees as to eliminate Bark Beetle infestations from attacking other nearby trees.  Behavioral controls are an alternative.  Bark Beetles can attract others of the same species by emitting chemicals called pheromones.  Pheromone traps are excellent in determining the populations of certain beetles.  Placement and understanding of how to best use these traps should be best left to a pro.  Preventative Sprays, Trunk Injections and Soil Drenches can all be considered but only by a professional who has experience and knowledge of the many aspects for successful control.  Arbortech can provide successful control problems for Bark Beetles for many years.

(Malacosoma disstria)

What is a Forest Tent Caterpillar?

Forest Tent Caterpillar

Forest Tent Caterpillars are similar in appearance to both Eastern Tent Caterpillar and Gypsy Moths.  Unlike Eastern Tent Caterpillar, the Forest Tent Caterpillar does not make a silky tent.  This pest over winters in the egg stage preferentially on the outer canopy twigs.  These egg masses are covered in a foamy like substance call spumaline.  Egg masses contain 150- 200 eggs and usually start to hatch in April around the same time that leaves start to appear.  Forest Tent Caterpillars are defoliators of hardwood trees and can completely defoliate its host tree. 

How will I know if I have Forest Tent Caterpillar?

Usually most do not recognize Forest Tent Caterpillar until defoliation appears as hard-woods are usually taller trees, such as Oaks, Sugar Maple, Aspen, Basswood, Ash, Birch and Cherry.  The larvae are usually dark colored with white markings that resemble foot prints or keyhole shapes.  They have long hairs and blue stripes.

How can Forest Tent Caterpillar be controlled?

It is best to have a professional determine if you are dealing with an outbreak that can cause substantial damage to your trees.  On smaller properties it may be possible to gain control by simply removing and burning egg masses in the fall or winter.  In larger and more heavily wooded areas, mechanical controls are not practical and chemical controls may be warranted.  Arbortech can help you decide which means of control are best applied.  Trunk Injections and chemical canopy sprays using environmentally friendly products are highly recommended.  On smaller private properties trees can often withstand outbreaks as long as trees are healthy and vigor is up.  Feeding will help your hardwood friends, especially when dealing with pests like Forest Tent Caterpillar, which are cyclic pests.


Have you seen Spruce Galls on your Spruce trees?

Cooley Spruce GallAdelgid partial gall

There are two types of Spruce Gall Adelgids in our area, Eastern Spruce Gall and Cooley Spruce Gall.  Both insects can cause disfiguring damage to at least three varieties of Spruce and also will attack Douglas Fir.

Both Eastern and Cooley Spruce Galls cause cone type looking swelling of twigs on Spruce trees, which are often mistaken as Spruce cones, which are natural.

Both types of Gall insects overwinter on the host Spruce tree and become active. 

Cooley Spruce Gall will also use Douglas Fir as a place to overwinter.

Gall pests emerge in spring; they become active and start laying eggs.  When the eggs hatch and become crawlers, they start to feed on the new growth.  The feeding causes a disruption of normal cell growth, thus creating an unhealthy and unsightly Spruce tree.

When is the best time to control them?

Timing of control is best determined by the methods of control being used.  GDD’s (growing degree days) is a tool that can give the arborist a fix on when Gall insects are most vulnerable, usually early spring followed by fall treatments are affective.

What methods of control are used?

There are several control treatments available: Foliar Sprays, using Horticultural Oil and Dormant Oils, if timed correctly.

Soil and Trunk Injections and Drenches are also effective.

Hand picking Galls is a good control when Galls are green. 

In stands of numerous Spruce trees, it may be advisable to remove those trees that are heavily infested.

If trees are infested and not under a treatment program, it may be best not to fertilize them, as this may enhance the problem.

If Colorado Spruce are planted or grow near Douglas Firs, the problem should be addressed.

Do not use oil based sprays on Blue Spruce, as it will change the color of the foliage and can predispose trees to winter injury.

WINTER MOTH (Operophtera brumata)


What is a Winter Moth?

Winter Moth is becoming a serious pest in the Northeastern states especially parts of  New England and areas of Massachusetts.  

There are very few natural parasites which aid in controlling this pest.  It can be expected to become another heavy defoliator in the tri-state area.

Winter Moths love to eat Ash, Basswood, Maple, Oak, Apple and Crabapple leaves. Contrary to the name, Winter Moth, does most of its damage in the spring!

How will I know if my trees have Winter Moth?

2005 05 03 Wintermoth-001

Winter Moths in the adult flying stage can be seen flying around lights in October, November and into January.  Eggs are deposited in tree bark crevices, under bark scales and beneath a good hidden covered place.  

Eggs begin hatching in spring and eat their way into buds, traveling from bud to bud until leaves start to expand, at which time feeding becomes heavier and leaf defoliation occurs.  These voracious eaters will feed until mid-June, causing chewed and devastating leaf damage as can be seen in photo.

What can be done to control Winter Moth?

Cultural controls include mulching and fertilization, to boost vigor and allow trees to become less susceptible to heavy damage.

Chemical sprays and Trunk Injections provide excellent control but must be applied in and timely fashion and by experienced applicators such as those at Arbortech.



What is a Psyllid?

Also known as jumping plant lice, Psyllids are small host specific plant feeding insects.

Psyllids are sap sucking pests that can cause severe damage and death to the particular plants they desire.  On many of the landscapes we maintain, the Boxwood is a favorite host.

How will I know if I have Psyllids?

boxwood psyllid damage

If you have Psyllids on your Boxwood, you will see a cupping of the foliage as seen in the photo.  Yellowing foliage can be present as pests persist.  Defoliation of leaves will be obvious on plants with heavy infestations.

What can I do to control Psyllids?

There are several methods of control available using a variety of pesticides that can be applied as sprays or drenches.  The best treatment for your Psyllid problem would be best decided by a licensed pest applicator such as those at Arbortech.

© Chris Graham 2013