Arbour Crest

Pest Control

Which pest or disease are you battling?

Not sure? Just have a look through our detailed Pest Profile table!

PESTS: Aphids, Apple Maggot, Aspen (Poplar) Borer, Birch Leafminer, Blister/Gall Mite, Bronze Birch Borer, Pine Needle Scale,
Spruce Spider Mite, Western Tent Caterpillar, Yellow-Headed Spruce Sawfly

DISEASES: Black Knot Fungi, Dutch Elm Disease, Fire Blight




Cottony Ash Psyllid has over-taken the black ash and Manchurian ash in the City of Saskatoon. Pictured here is the effects the pest has on a leaf. Essentially, curling it up or “cauliflower-ing” it. 

We are hoping for a cold winter this year as the cooler temperatures will help reduce the population overall.

Click here for more information on this destructive tree pest.





And don’t forget about what’s new for Pest Control and Plant Health Care at Arbour Crest this year!

BioForest Tree Injection System for Pest Control-
Our new system for delivering effective pest control is the first in the province and is here to suit your needs. Our system allows us to inject the product into your trees systemically with little to no interference to the environment or beneficial insects. Treatments can last up to two years, further reducing environmental effects and lowering cost.

Tree Risk Assesments-
We are pleased to announce that three of our certified Arborists have earned their Tree Risk Assesment Qualification credentials. This credential promotes the safety of people and property by providing a standardized and systematic process for assessing tree risk. The results of a tree risk assessment can provide tree owners and risk managers with the information to make informed decisions to enhance tree benefits, health, and longevity.



To request a quote please click here.


Or phone our office at 306.242.TREE(8733) for more information on any of our services
or to book a consultation with an ISA Certified Arborist.




INSECT PESTS Identification & Damage Biology & Control

-Generally black/gray and yellow/green, less than 3mm with long legs and antennae
-Typically found on broadleaved trees and shrubs with blotchy dead leaf tissue
-Repeated infestations can cause eventual branch dieback and early leaf drop


-Multiple life stages can be present and they occur in large colonies on new growth
-Systemic insecticides, sprays (for adults) and bioinsecticides
-Multiple life stages may require multiple applications

Apple Maggot

-Adults of this insect are about 5mm long and have a dot on their thorax and a black banding like an “F” on their wings
-White­-yellowish worm like larva with not so noticeable head that feed on the apples causing brown spots with tunnels through fleshy tissue
-Found in primarily Apples and Hawthorns


-One generation per season
-Adults emerge in early July before laying eggs under Apple skin
-Larva will overwinter in soil
-Foliar sprays to control adults, no systemics suggested for edible species
-Traps and decoys for egg laying females
-IPM plan is suggested for this pest

Aspen (Poplar) Borer

-Adults approx. 1″ long and are dark grey with small orange spots on their wings
-Larvae white, about 1 1/4″ long, legless, and yellow­-white in color
-Heartwood boring insect creating cavities
-Frass (wood dust, cuttings) at base of tree


-Emerge June until August, and lay eggs in slits they have cut in the bark
-Egg­laying females are most likely to be attracted to open­grown and single trees in partial to full sun
-Systemic insecticides, sprays (for feeding adults)

Birch Leafminer

-Adult resembles a black wasp (about 3mm long), larva are flat and white (5-7mm long)
-Blotchy dead leaf tissue.
-Repeated infestations can cause eventual branch dieback


-Eggs hatch early June, two generations per year
– Larvae overwinter in soil/fallen debris
-Systemic insecticides, sprays (for adults), bio-insecticides also available

Blister/Gall Mite

-They are not noticeable with naked eye
-Feed/hide beneath leaves causing a blister to form
-Reduce the amount of useful leaf surface in broad leaf trees and some conifers
-Eventual branch dieback possible


-Larvae overwinter in soil/ fallen debris  and egg hatch early June, two generations per year
-Systemic insecticides, sprays (for adults), bio-insecticides also available.
-Typically do not require treatment however can pose significant health risks if left untreated (long term)

Bronze Birch Borer

-Adults 1⁄4″ to 1⁄2″ long dark colored beetles , larvae up to one inch long when fully grown, pale white with a flattened body and two pincer­like tails at back
-Secluded branch dieback from boring D shaped holes in trunk and limbs
-Kills vascular system reducing nutrient transport


-They pupate in spring and start to emerge as adults in early June
-Larval stage is the most destructive and difficult to control
-Systemic insecticides, sprays (bio-insecticides available)

Pine Needle Scale

-Nymphs are tiny yellow flat crawlers, adults females are oval wingless insects up to 3mm long
-Usually noticable as a white dotted cover over tree or shrub
-Sucks juices from needles reducing vigor and health leaving behind yellow and brown needles


-Egg hatch occurs in the spring
-Females settle and secrete waxy scale­ like coverings over their bodies and produce a sac of eggs under the scale
-Systemic insecticides, sprays in spring durring crawling phase, pruning

Spruce Spider Mite

-Scarcely visible to naked eye and appear greyish with eight legs (some species red)
-With high population density, webs will form among needles and defoliation of evergreens will occur
-Will affect health and vigor after repeated infestations
-Large populations require control due to extent of dieback that occurs (spreading outward and upward)


-Eggs over winter in crevices and hatch mid mid-May
-Nymphs and larvae suck juices from needles
-New generation every 3 weeks
-Systemic insecticides, sprays (bio-insecticides available)

Tent Caterpillar

-Young larvae are black, mature larvae 1­2 1/2″ with four yellowish­brown stripes down body containing diamond shaped dots
-Adults are rusty red to pale in color.
-Defoliation of broad leaved trees
-Will affect health and vigor after repeated infestations


-Egg hatch when foliage starts to emerge clustering on silken webs at night
-One generation per year, adults emerge in Late June/ July­
-Systemic insecticides, sprays (bio-insecticides available)

Spruce Sawfly

-Larvae look like caterpillars and are normally grayish-green and have a light stripe down the back, a light stripe along each side followed by a dark green stripe
-Full grown larvae are about 1″ long


-If the population levels are consistently high in your area, treatments are suggested to bring the population down to an acceptable threshold
-Most treatments take place in June (or prior to) when the trees are leaved and larvae are in their destructive stage



DISEASES Identification & Damage Biology & Control
  Black Knot Fungi

-Infects chokecherry, pincherry, wild cherry, cherry and plum trees
-A green swelling appears at first mostly in the fall, as the knots mature they turn black
-Easily spreads and appears on all sizes of branches and twigs
-If the fungus circles the entire branch, it will die, and severly diseased trees may have to be removed altogether


-Caused by a fungus that is spread by wind and rain
-Once it begins growing on a black knot it produces fruiting bodies that spread the disease
-Can also be spread by contaminated pruning equipment
-Can be pruned out if caught early enough

  Dutch Elm Disease

-Vascular infecting fungi that blocks the transport of water and nutrients
-Devastating for Elm trees in North America
-Symptoms include yellow flagging in foliage, browning of leaf tissue (not to be confused with Bacterial Leaf Scorch or Elm Yellowing)
-No standard dieback pattern (this is affected by where the disease was introduced to the tree)


-Arrived in North America in 1930s, it is transferred through root fusion and insects from infected trees such as the Elm Bark Beetle
-Preventative macro injections pre­-infection
-Insect control through micro injections will limit insect vector populations – reducing root graft potential in boulevard trees
-Early detection and removal of infected species is crucial.
-Provincial laws regulating disposal of and inoculation of suspected trees

  Fire Blight

-One of the most destructive diseases facing fruit trees
-Tips of twigs form “shephards hook” leaving foul smelling brown foliage retained
-Systemic disease threatens its vascular system and dieback of new growth sometimes causes oozing to drip and spread to lower foliage


-Bacteria overwinter in the bark at the edge of cankers formed during previous growing seasons
-Topical sprays are generally used to reduce effectiveness of re-innoculation from external oozing
-Best controlled through an IPM plan