Insect Control and Prevention for Trees

Tree Care and Tree Insect Treatments - Aphids, Spider mites, Ash Sawfly & More


Control and prevent a wide variety of insects on your deciduous, coniferous, and fruit-bearing trees.

Many trees in Colorado get attacked by insects every year. These damaging tree insects might include aphids, curl aphid, mealy bug, leafminers, bronze birch borer, elm leaf beetle, elm scale, honeylocust plant bug, juniper scale, kermes scale, cottony maple scale, spider mites, oystershell scale, ash sawfly, emerald ash borer and many other insects. Even though these insects rarely kill a tree they can cause severe stress and can reduce the trees ability to fight other biotic or environmental conditions like heat and drought stress.

A tree that suffers from insect pressure will grow much slower than a healthy tree and insect pressure on trees can reduce the growth rate by as much as 70%. It is rare, but trees that are left untreated over several years can even be killed by insect pressure.


Organo-Lawn is your local tree care expert for tree pest control. Call with questions about tree care in Boulder area (303)499-2000 or Fort Collins area (970)-225-9425.

Tree Pest Control Service - Boulder

Aphids are severely damaging this tree in Boulder, Colorado. Aphids can quickly damage a tree because they can reproduce at the rate of 20 babies per day, per aphid.

Tree Pest Control Service - Fort Collins

This leaf on a tree in Fort Collins is covered in honeydew which is the shiny and sticky secretion left behind by aphids.

  • Orthene Soil Injection - Orthene is a reactive insecticide for tree care and is fast acting insect control for many problematic tree insects including aphids, spider mites, ash sawfly, and other insects.
  • Merit Soil Injection - Merit is a preventative insect control for many problematic tree insects including aphids, scales, ash sawfly, emerald ash borer, spruce gall, and many other damaging insects on trees.
  • How to Calculate the Diameter Breast Height for Orthene and Merit Treatments - We determine pricing of our tree care treatments based on the trunk diameter.
  • Tree Care Chart - This tree care chart explains which tree pest control is needed.
  • EcoTrol - Ecotrol is a 100% organic insecticide for fruit trees.

FAQ - Insect Control - Trees

Can I keep insects from attacking my tree?

  • Yes, there are two different preventative treatments that we use for insects, Merit and Safari. They work on both deciduous and coniferous trees. They can control many insects, but these insecticides do not control spider mites, and certain borers. Safari works well on scale. Merit works well as preventative for the Emerald Ash Borer. These systemic insecticides will protect the tree for one year.

Is the insect control for trees safe for bees?

  • We understand that Merit and Safari are in the neonicotinoid family of pesticides. We understand that neonicotinoids are highly toxic to honeybees and at Organo-Lawn we greatly care about the safety of honeybees. We have researched the use of Merit and Safari as a soil injection and have found no evidence that that the honeybees come in contact with the insecticides Imidacloprid or Dinotefuran.
  • The reason for this is because the insecticide cannot penetrate the abscission layer of the tree therefore it cannot get into the flower or pollen of the tree. If we find scientific evidence that states otherwise we will discontinue the use of these insecticides.