Plant Health Care
General Tree and Plant Health Care
The most important factor in keeping your trees and shrubs disease and pest-free is maintaining their health and vigor.
Colorado summers in the front range are often characterized by long hot and dry spouts. Proper irrigation of your tree will help keep it healthy and vigorous, allowing it to naturally resist pest problems. Newly planted trees should be watered often, every few days or whenever soil appears dry. Established trees should be watered every 2-3 weeks or more in the summer depending on rain and humidity levels. Remember evergreen trees require water year round. Avoid irrigating foliage and the trunk of the tree as these practices could lead to fungal/bacterial infections.
Colorado summers in the front range are often characterized by long hot and dry spouts. Keeping your tree properly irrigated will help keep your tree healthy and able to resist pest problems. Newly planted trees should be watered often, every few days or whenever soil appears dry. Established trees should be watered every 2-3 weeks or more in the summer depending on rain and humidity levels. Remember evergreen trees require water year round. Avoid irrigating foliage and trunk of the tree as these practices could lead to fungal/bacterial infections.
Mulching around a tree can help retain moisture in the soil and act as a buffer against extreme temperature variation. It also provides a barrier protecting the trunk of the tree from mechanical damage from lawn mowers and weed eaters, while at the same time reducing soil compaction from these machines. Decomposing mulch can also provide nutrients and increase soil microbial activity. The recommended mulching depth is 2-4 inches evenly around the tree. Remember to keep the trunk base and root flare of the tree free and uncovered by dirt and mulch to avoid bacterial/fungal infection.
Pruning is an important part of keeping a tree healthy and vigorous. Removing dead or broken branches and stubs reduces the risk of disease entering the tree. Thinning and removing redundant branches can also encourage new growth and avoid future damage. Trees which are susceptible to fungal infection should be pruned in late winter, early spring when the new growth of trees will begin to heal the wounds as quickly as possible.
We carefully consider all available pest control techniques and integrate them in a way which minimizes health risks to humans, animals and the environment.

Colorado Insect/Disease Problems
Sap sucking insects which can cause unsightly damage to trees and shrubs; doesn’t generally threaten the life of the tree.
Symptoms: Leaf curl as chlorophyl is sucked from the leaves, honey dew (clear saplike waste from aphid activity), increased activity from wasps, ladybugs or hoverflys which are natural predators.
Treatment: We recommend and most often treat aphid infestation with the systemic insecticide Imidicloprid. This chemical is uptaken by the tree and becomes effective within a few weeks. Any insects which try to infiltrate or eat the tree will die. This treatment is also effective in treating Emerald Ash Borer.
For a more immediate treatment we offer foliar sprays with permethrin/bifenthrin. Sprays last 1-2 months while a systemic injection will last a full year and is usually applied in late winter.
A non-native insect which was found in Boulder, CO in September of 2013 and has since spread to the Broomfield, Longmont, and Gunbarrel areas. Infestation results in certain death of the tree and often takes a few years to notice, which is why preventative treatment is recommended. Emerald Ash Borer is still rather rare in our area, but remains a very serious and fatal emerging threat. The ash tree populations of other regions in the United States and Canada affected by this invasive species have been utterly devastated, and we can expect that more regions will fall victim to the EAB in our own state.
Symptoms: Canopy die back, borer holes in the shape of a D.
Treatment: We offer a 1 year soil injection treatment option with Imidicloprid which has proven to be over 95% effective and also a 2 year trunk injection treatment using TreeAge which has shown to be 99% effective.
Visit our EAB Treatment page, or visit the official State of Colorado site for information on Emerald Ash Borer in Colorado: https://www.colorado.gov/agplants/emerald-ash-borer
A more common form of borer which tends to attack younger or weaker trees.
Symptoms: Canopy die back. Circular boring holes in trunk or large branches where sawdust like material is expelled and often piles up a the base of the tree.
Treatment: We offer a trunk spray which is applied in early spring (May) and often a second time in the summer. Systemic insecticides have not proven to be effective.
Bark beetle (1/8 to 1/3″ length, Black/brown in color) which destroys the cambium and introduces blue stain fungus (Fatal).
Symptoms: Browning needles, “pitch” tubes in trunk (yellow mounds of sap being excreted).
Treatment: Early May – mid June
We offer a preventative trunk spray treatment using permethrin. This residual pesticide has low mammalian toxicity and is commonly used in the agricultural and medical sectors.
Tiny bark beetle (1/8 – 3/8″ in length) also known to introduce the fatal blue stain fungus to trees.
Symptoms: Canopy dieback, small shotgun-like exit holes in bark.
Treatment: Early May – mid June
We offer a preventative trunk spray treatment using permethrin. This residual pesticide has low mammalian toxicity and is commonly used in the agricultural and medical sectors.
Symptoms: Pink to red resin and pitch usually found near the base of the tree.
Treatment: Turpentine beetles almost always attack stressed trees. Proper irrigation and maintenance of soil and surrounding area are the best ways to maintain the trees vigor and prevent infestation. We offer a trunk spray with Tenguard as an effective means of killing any beetles which have bored into the tree and preventing future infestations.
Symptoms: These borers generally produce tunnels just below the soil surface on the root flare or lower part of the trunk. Amber-colored jelly-like sap generally protrudes from entrance holes (not to be confused with Cytospora Canker which is a harder ooze).
Treatment: Proper planting techniques are essential to avoiding Peach Tree Borer. Trees should be plant at or above the soil grade with the root flare exposed. We offer a trunk spray with permethrin as a preventative control. Inserting wire into holes to pierce larvae and burying mothballs below the trunk have also proven to be effective controls.
Symptoms: Tent like webs that appear around foliage, results in foliage loss when larvae emerge.
Treatment: Systemic injections with Imidicloprid or foliar sprays with Tenguard are highly effective for management.
Small soft, scale looking insects which are light brown with a white outline. Severe infestation can be fatal.
Symptoms: Yellow leaves, premature leaf drop, black sooty mold, stickey honeydew.
Treatment: The best form of treatment is by systemic soil injection using imidicloprid. This is most effective when performed in early spring as it requires a few weeks to take effect. Early spring dormant oil treatments have also been successful in curbing infestations as have summer sprays with permethrin.
Symptoms: Shotgun-hole like holes and brown botches in foliage.
Treatment: Predatory wasps and birds often control populations effectively. If a severe infestation occurs, we recommend treating your elm with a systemic insecticide or foliar spray.
Symptoms: Branch dieback, scales introduce a bacteria which appears as a sticky “drippy blight”, can be fatal.
Treatment: The best form of treatment is by systemic soil injection using imidicloprid. This is most effective when performed in early spring as it requires a few weeks to take effect. Early spring dormant oil treatments have also been successful in curbing infestations as have summer sprays with permethrin.
Symptoms: A moth whose larvae feed on fruiting bodies causing holes. Damage can result in loss of fruit but generally won’t affect tree health.
Treatment: Preventative pesticide/dormant oil spray in early spring
Symptom: Moth which destroys branch tips. Small boring holes can be visible in branch tips. Can be very destructive as it often “tops” or kills central leader in tree.
Treatment: We offer a pyrethoid spray to prevent any moth entering the tree and to kill any which currently reside. Parasitic wasps offer an excellent natural control.
Symptoms: Zimmerman pine moths produces masses of pitch (sap) on the trunk often where branches are attached. The pest doesn’t cause significant damage and generally won’t affect tree decline.
Treatment: Zimmerman Pine Moth usually attacks stressed trees. Proper irrigation and maintenance of soil and surrounding area are the best ways to maintain the trees vigor and prevent infestation. We offer a trunk spray with Tenguard as an effective means of killing any beetles which have bored into the tree and preventing future infestations.
