This page can help you identify simple problems that happen in every landscape. In caring for those problems and promoting proper tree growth, you are helping to enhance the benefits of trees.
Trees have been held in high regard throughout the ages. They have held a special place in many cultures and traditions. They have been used as religious symbols and as landmarks. They are a living tribute that will affect the lives of generations to come.
President George Bush, Sr., in a speech encouraging tree planting and care, said, "...the forests are the sanctuaries not only of wildlife, but also of the human spirit. And every tree is a compact between generations."
|An Arbor Day tree planting
There are so many conditions that affect our landscapes. High winds, cold temperatures, high soil pH, low precipitation levels and heavy clay soils are just some of the factors that work against our landscapes. For information on trees not recommended as street trees, public right-of-way planting specifications and trees to avoid, visit our planting specifications page.
An ILLUSTRATED GUIDE TO PLANTING TREES with step-by-step instructions and photos depicting the procedures involved in planting balled-and-burlapped trees is now available.
- The planting hole should be 2 times the size of the root ball and never deeper than the bottom of the root ball. Loosen or scarify the soil on the sides of the planting hole; this helps the roots establish more rapidly.
- Be very gentle when handling any root ball. If a plant is planted from a container, gently remove the container and tease or loosen any spiraling roots. If the tree is a balled-and-burlapped tree; place the tree next to the hole and remove the bottom 1/3 of the wire basket, set the tree in the hole gently, fill hole approximately halfway with soil, then remove the upper 2/3 of the wire basket.
- Backfill with existing soil and gently pack the soil. Do not compact the soil which will make water penetration difficult. If amending soil with organic material, never use more than 1/3 organic matter to existing soil.
- Build a water retention ring with the remaining soil and fill this ring with water. Proper watering is critical to a tree’s survival. Check with your local nursery for the watering needs of specific trees.
- Apply mulch to the inside of this ring, never more than 3" thick. The mulch will help to reduce the weed population, keep lawn mowers and weed eaters away from bark and help the tree maintain moisture levels.
- Due to Greeley’s high winds, it helps to stake and guy a tree for its first year or two of establishment. It is recommended to use nylon straps, always allow for growth of the tree and never put constricting wires in contact with the bark of the tree.
- Prune only what is needed; remove crossing branches and double leaders only. After several years of establishment, pruning is usually required.
- Planting on public right-of-way requires a landscaping permit prior to planting. If you would like to obtain information on a landscape permit, visit the Rights-of-way permits page.
- Before selecting a tree, look at the site where you will be planting. Decide about size, shape and other features (color, flower, fruit, drought-tolerance, etc.) that you want in a tree.
- Visit our Trees for Greeley page which will aide in the selection of a tree for your site. Also, consult with your local nurseryman or County Extension office.
Making a branch collar cut
For pruning diagrams and to view technical fact sheets on pruning, visit Colorado State University.
For interactive and fun pruning instructions and video, visit The National Arbor Day Foundation
, and launch the pruning program.
- Training a tree by properly pruning it when it is young will minimize future maintenance problems. Also, pruning will create a better-formed and healthier tree.
- Be sure to remove all dead, diseased and broken branches. The remaining branches will become healthier and better able to withstand heavy snow buildup.
- When pruning larger branches, first make an undercut about six inches from the main branch. Cut it off from the top down, and then remove the stub at the branch collar. This method prevents stripping of the bark.
- Never leave a stub; it will never callous and can become an entry point for decay-causing organisms. Proper cuts will callous properly. Do not apply tree wound paint. Research reveals that trees callous faster and are less susceptible to infection when no wound dressings are applied.
- It is also important not to make flush cuts that wound the tree. Use a professional, licensed tree service when the job is beyond your ability or skill.
- All tree service firms working in Greeley must be licensed and insured. Use only licensed tree service firms.
- Remember, Never Top Trees! Topping is an unacceptable method of pruning which increases a tree’s maintenance needs and creates very weak and hazardous branches.
Finished branch collar cut
Watering and Nutrition
To learn more about Xeriscaping, visit the UNC/City of Greeley Xeriscape Gardens web page.
Newly planted tree getting a drink
- On a new tree, create a basin or "tree well" around the base of the tree. A young tree requires a basin just outside the root ball. Water the tree slowly. Let the water run at a trickle into the basin and soak the soil. You cannot water trees too much at one time; however, you can water too often. Generally, it is best to water newly-planted trees at least weekly for the first month and once every two or three weeks for the remainder of the year. All trees take special care in watering the first 2-3 years to become established. Don't forget to winter water ALL trees.
- Once trees become established, water according to the requirements of the tree. Some trees grow better in drier sites and some in moist sites. Consult the Trees for Greeley page to help determine the watering needs of your tree(s). Also, contact the Greeley Water Department for information on "Xeriscape" (lower water need) landscaping.
- Your soil texture will determine the watering interval. In this area, the soil texture ranges from heavy clay to sand. In heavy clay, watering may be done less often, but run-off problems may require watering in two half-hour periods in order to achieve the suggested soaking. Sandy soils, on the other hand, will dry out more quickly requiring you to water more often.
- When the nights turn cool and the days shorten, it is best to reduce watering trees and other plants. Labor Day is a good reference point. This is the time when plants prepare for winter through a process referred to as "hardening off."
- Watering and fertilizing encourage continued growth, and trees cannot accomplish their natural anti-freeze preparation before frost begins. This can cause winter kill. Generally, it is best to water once a month in the winter and only after trees have hardened off.
- Keep in mind that wind, temperature, exposure and drainage also influence watering needs.
- Always allow for lawn irrigation and natural watering by rain or snowfall, and adjust your watering schedule accordingly.
- Now available is a detailed information on watering trees from Denver Water.
For more information on fertilization and using pesticides to care for your trees, click here fertilizers and pesticides.
There are any number of things that can affect plant health.
Engraver beetle exit holes
However, there are usually simple factors that introduce disease and insects. Watering and treating or "spraying" your trees or plants may not always be the answer.
Try to identify the causal factor and then create your management program.
Contact the Forestry office by email or phone to get more information on obtaining help with your landscape.
Requests are received from citizens to inspect trees or shrubs on their property. A staff arborist then visits the site and advice is given concerning potential insect, disease, structural and/or cultural problems. Recommendations are then made toward corrective actions that should be taken to alleviate or prevent particular problems.
Every effort is made to provide advice or information by phone, mail or email at no charge. On-site consultations will be arranged around other duties, typically at no charge. Consultations may be performed by any of the qualified full-time staff, keeping in mind that it is very difficult for us to schedule appointments.
To learn more about the following problems, visit the Colorado State University Cooperative Extension Site.
Common Diseases In Greeley
Fireblight - Crabapples, Hawthorns, Mountain Ash, Apples, Pears
Cytospora Canker - Aspen, Cottonwood, Poplars, Apple, Cherry, Honeylocust, Peach, Plums, Birch, Willow, Siberian Elm, Spruce, Silver Maple, Mountain Ash
Thyronectria Canker - Honeylocust
Dutch Elm Disease - American and English Elms
Chlorosis - Aspen, Silver Maple, Austrian Pine, Crabapple, Red Oak, Pin Oak
Bacterial Wetwood - Wide range of trees.
Pine Wilt - Scots Pine
Thousand Cankers Disease - Walnuts
Boxelder bugs in early fall
Many insects attack trees in only a secondary capacity. In other words, they are there because the plant has already been predisposed to a particular problem and is under a great amount of stress.
Two of Greeley's major insect pests, the European Elm Bark Beetle and the Spruce Ips Engraver Beetle, both attack trees under stress. The Elm Bark Beetle transmits Dutch Elm Disease and the Ips Beetle destroys Spruce. Just as preventative maintenance works with automobiles, plants free from insects and disease work the same way. Pay attention to proper watering practices, planting and pruning techniques, fertilization, and sound tree selection/placement.
For more information or to help diagnose your own insect problem, visit the Colorado State University Cooperative Extension Site.
Common Insects In Greeley
Aphids - Wide range of plants
Elm Leaf Beetle - Elms
Elm Flea Weevil - Elms
Elm Bark Beetle - Elms
Elm Leaf Miner - Elms
Cooley Spruce Gall - Spruce
Ips Engraver Beetle - Spruce
Boxelder Bug - Boxelders BR>Hackberry Nipple Gall - Hackberry
Spider Mites - Spruce, Honeylocust
Poplar Twiggall - Aspen
Scale - Aspen, Elms
Pinyon Pitch Mass Borer - Pinyon Pine
Zimmerman Pine Moth - Austrian Pine
Lilac/Ash Borer - Lilac, Ash
Cynipid Wasp - Bur Oak
Mountain Pine Beetle - Scots Pine, Ponderosa Pine, Pinyon Pine, Bristelcone Pine, Lodgepole Pine
Pine Wilt Nematode and Pine Sawyer Beetle - Scots Pine
There is a difference between environmental and mechanical damage. However, understanding these important and basic tips can help you maintain control over these issues.
Sunscald - Sunscald happens during cold, bright days in winter. Young, thin-barked trees are most susceptible. During warm winter days, cells and tissues become activated. When freezing temperatures develop overnight, those cells freeze. Sunscald can be prevented. We recommend the use of commercial tree wraps, which are available at most garden centers and plant nurseries. Wrap trees from October through April. Begin at the base of the trunk and overlap wrap spiraling upward; secure at the first branch union with masking tape. Wrap trees at least the first two years after planting or transplanting. DO NOT leave wrap on all year round. This will restrict tree growth and increases chances for attack from disease and insects.
Drought/Overwatering Injuries - All plants can be injured by receiving too much water just the same as if they do not receive enough. Most insects and disease will not infest healthy trees. By not having the proper watering schedules for your particular landscape, your plants are susceptible to attacks from insects and disease. Basically, proper watering helps keep the plant's immune system working properly. If planning a new landscape or working with a fairly young landscape, utilize all resources available to discover what watering requirements are necessary for each plant. Mature landscapes offer little opportunity to re-design watering zones or schedules. Talk to a professional about making watering changes. Once a landscape adapts to a particular schedule, stress may be induced if that schedule is changed. Remember, ALWAYS water the ENTIRE year. During warm dry spells in the winter, drag out your hose and give your landscape a good soaking.
Frost Damage - Frost damage occurs with both early Fall frosts OR late Spring freezes. Avoid heavy nitrogen applications to your landscapes after July. This will help your plants to begin dormancy and will not encourage new growth at an inappropriate time. Spring freezes typically cause more noticeable damage than fall. This is a time of strong growth. Frost injuries can be difficult to prevent; however, ideally you should plan to use plants that fit our climate and hardiness zone. Be wary when using tender plants; they will need proper protection according to their growth habits and requirements. Each plant has its own micro-climate in which it will perform better.
Damage caused by
weed eater/lawnmowerWeedeater/Lawnmower Damage -
This damage is easily prevented. Ideally, you need to maintain a "tree ring" around the base of each tree. You can do so effectively with herbicide (weed and grass) destroying chemicals. Carefully prune all basal sprouts and suckers off of the tree before applying chemicals. Providing this ring around trees helps to eliminate the need for weedeaters and lawnmowers to get too close to the base of the tree, doing fatal damage. Also, shrubs and shrub beds should be isolated from turfed areas. Do so with edging materials of your choice, and place a wood chip mulch inside your shrub bed.
Herbicide Damage - This damage occurs from the improper use of chemical weed and pest controls. Diagnosis of the problem is not always simple. A complete history of maintenance practices and technical information is needed to properly diagnose the problem