Watering

Vertical Mulching: Vertical mulching is a technique used to help alleviate soil compaction in the critical root zones of trees. It is also effective to improve soil conditions after construction projects.  Compacted soil can be detrimental to a tree’s health by reducing the movement of water and oxygen throughout the soil– both vital to the tree’s wellbeing.  Vertical mulching involves removing columns of poor-quality soil around the tree in a radial or grid pattern. Holes are then filled with compost. Vertical mulching provides many benefits, including providing necessary nutrients, soil aeration, and allowing deeper water penetration. Please watch this video for more information.  

Nitrogen fertilizer generally increases canopy growth, resulting in a decrease in root growth. Because the trees we plant are young and still in their establishment phase focusing on root growth, fertilizer is not recommended. If soil conditions are poor, then see Q1: How to improve soil conditions through vertical mulching. One of best ways to help your tree is to continue to replenish the organic mulch layer around your tree.  

For more information on fertilizing shade trees, review https://cmg.extension.colostate.edu/Gardennotes/635.pdf. 

No. Rocks used as a ground cover are detrimental to trees and shrubs. Rocks retain heat, which in turn raises the soil temperature and increases evaporation; this leads to stressed, thirsty plants that require even more water. Rocks also will not provide any essential nutrients and can change the soil chemistry which can be unfavorable for many trees. While rocks and xeriscape lawns can be a way to conserve water in other areas of your garden, it is essential that the area with your tree roots is covered with mulch or other organic material.  

Grass around the base of the trunk is not recommended. Grass competes with young trees for moisture and nutrients in our already water–scarce climate. Additionally, having grass close to your tree increases the risk of mechanical damage to the trunk from lawn mowers or string trimmers. Maintaining a ring of mulch around the base of the tree is the best groundcover in our urban setting.  

Grass around the base of the trunk is not recommended. Grass competes with young trees for moisture and nutrients in our already water–scarce climate. Additionally, having grass close to your tree increases the risk of mechanical damage to the trunk from lawn mowers or string trimmers. Maintaining a ring of mulch around the base of the tree is the best groundcover in our urban setting.  

Your tree will likely require more water than our guidelines because of the surrounding pavement/metal. Pavement and metal retain more heat, which raises the temperature, increasing evaporation. It’s important to check the soil moisture to determine when your tree needs water in these types of planting locations.  

Particularly wet and heavy snow can catch on the branches of young trees, causing them to bend and sometimes break. When this type of snow occurs, gently shake the branches of the tree as soon as possible to relieve the weight and prevent damage. If a branch is broken, prune the branch to create a clean cut.  

You can easily check to see if a young tree is alive by a flexibility or bark scratch test. Branches that are alive should be pliable and bendable. If they snap when you bend them, they are dead. Check as many branches as possible in the crown of the tree to see how many are alive. You can also perform a bark scratch test using your fingernail or knife: GENTLY scratch off a tiny section of the outer portion of bark – it should reveal green underneath. If there is no green, then that branch or trunk is likely dead. 

Most likely, no. It’s not uncommon for some trees to experience this after planting. Transplantation can be a stressful event for trees and some will drop their leaves to focus their energy elsewhere, like in growing their root system. Please continue to water your tree even if the leaves drop. You can determine if the tree is still alive using the methods in Q1: I think my tree is dead. How can I tell? 

The suckers growing from the base are a sign of stress, most likely from the tree not getting enough water. If the trunk and crown of the tree are still alive, prune back the suckers and make sure your tree is getting enough water. See Section 1: Watering, Q1: My tree was just planted. Do I need to water?  above to ensure that your tree is getting adequate water.

The suckers growing from the base are a sign of stress, most likely from the tree not getting enough water. If the trunk and crown of the tree are still alive, prune back the suckers and make sure your tree is getting enough water. See Section 1: Watering, Q1: My tree was just planted. Do I need to water?  above to ensure that your tree is getting adequate water.

We have a number of insects on the front range that like to nibble on leaves. For healthy trees, this is likely not a cause for concern and is a sign of an ecosystem at work. CSU Extension provides information on many of our most common pests. Learn more about the  Japanese Beetle and Elm leaf beetle.  

Healthy trees should have the ability to compartmentalize most wounds, as long as they aren’t too severe. Do not wrap or paint the wound as this could create a warmer, moister environment for diseases.  Monitor the wound and allow the tree to recover on its own.