Expert Tree Care from Certified Arborists in St Charles, Naperville, Downers Grove and Surrounding Areas!

Commonly Asked Questions about Tree Care and Tree Service

When trees turn fall color early, it’s a sign that they are in trouble. Most trees will turn color in October. But, if your trees are turning color early, such as in August, you’ll want to get them checked. This could be caused by a variety of factors.

When trees turn early it’s usually a sign that the root system is being stressed. Several causes include:

  • Newer neighborhoods (under 30 years old) with soils heavy in clay are always a concern. Many property developers have a habit of stripping off and selling a property’s choice black dirt, leaving only 4-6 inches of this premium soil. That might be enough soil to grow grass, but it is hardly enough to expect trees and shrubs to flourish long term. Trees in these conditions usually grow and look good for 5-10 years, but once their initial growth spurt passes they require the proper nutrients to continue toward a long, healthy life, or they begin to suffer.
  • Other situations that might be causing distress in your tree include girdling roots, construction damage, and herbicides (weed killer).

Given the variety of possible causes, a Certified Arborist should always be consulted. Tree care is a highly complex field in which knowledge and experience mean everything.

The optimal solution is to have your trees fed by a professional company that understands the specific needs of trees in urban environments such as ours. Your trees’ chances of survival increase significantly with proper, professional, and high-pressure root fertilization with the highest quality products.

Please visit our Root Fertilization page for more information.

Every year we get numerous calls asking why a tree’s leaves or needles are yellowing and falling in abundance at seemingly odd times. There are a variety of reasons for tree stress, which are discussed at length in other pages on our website. Please visit Apple Scab Disease, Anthracnose Fungus, Early Fall Color and Iron Chlorosis.

Sometimes, however, early leaf drop or needles falling may just be a natural occurrence. Here are just a few examples of leaf/needle drop that affect certain species of trees.

River Birch
If your River Birch looked really thick and full in the spring, but once the summer heat arrived the area around the tree became littered with fallen, yellow leaves, there could be multiple reasons for this occurrence.

  • It is fairly common for River Birch leaves to turn yellow due to Iron Chlorosis, caused in large part by poor soil conditions. Chlorosis is distinguishable from ‘natural’ shedding by the fact that the veins of the leaf will stay green, but the tissue in between will turn yellow.
  • When soil moisture begins to dissipate, the tree realizes that it does not have enough moisture to sustain that full crop of leaves it originally produced. The tree will then shed a lot of its interior growth to protect itself during the heat of summer.

Crabapple Trees
Crabapples, which are susceptible to Apple Scab Fungus, lose leaves all summer long due to this disease. When a Crabapple tree has Apple Scab Disease, it generally loses 50% to 90% of its leaves throughout the summer. However, when we treat a Crabapple tree it will retain 95% of its leaves.

Clients get nervous when the leaves of trees that we are treating for Apples Scab begin to yellow and fall. It’s understandable that they think the spray applications may not be working. Rest assured this is not the case! The main reason for this leaf loss is that the Crabapples that we treat are so thick and full of leaves (which they have not experienced in years prior to our treatments) that the inner leaves on the tree no longer receive the sunlight they require due to the now thick canopy, so they yellow and drop.

Scotch, Austrian and especially White Pine
Inner needle shedding is a normal process, even on the healthiest of pines. When we look at the inner areas of any mature conifer, evergreen or pine tree, there is no live, green growth in there. This is because pine trees only allow themselves 5-7 years of growth before they naturally shed their inner needles.

As the tree keeps pushing out new growth year after year, the inner areas become more and more shaded. The needles yellow and drop due to the sunlight’s inability to reach them. This situation may occur to a minor extent on a yearly basis, but then, every 3-4 years, the dieback may seem excessive.

This looks scarier than it is, although do not completely discount the possibility that the situation could be due to a combination of other factors such as Borers, Sphaeropsis Fungus or poor soil conditions,

Professional Root Fertilization is the best way to ensure the health of urban trees and to protect them from the stresses they endure.

Every year we receive numerous phone calls from homeowners claiming their trees’ leaves are under attack from thousands of bugs. Upon inspection we identify the ‘culprit’ as Leaf Galls, which is not an active insect problem.

Leaf Galls appear as bumps on the leaves. They can be red, green or black and can be shaped like little round BB’s or like a Unicorn horn sticking out of the leaf. Galls can be so numerous on a single leaf that the distorted leaf is unrecognizable. As the summer progresses and the galls dry out they begin to break free of the leaf and fall away. This leaves holes in the leaves that can be mistaken as chewing insect damage.

Galls can appear on many varieties of trees but are most common on Maples, Oaks, Lindens, Hackberry and River Birch.

Leaf Galls are areas of accelerated plant growth. Galls are caused by tiny wasp-like insects and mites that are not particularly damaging to the trees. The galls develop long after the initial feeding cycle of the insects that caused them. The problem is more unsightly than anything


Homeowners often question our “no treatment required” diagnosis after receiving conflicting recommendations from other companies. But trust us… leaf galls will not harm your tree in the long term, and we refuse to profit from unnecessary treatments. Tree Green prides itself on honesty and integrity.

We refer to the proper method of mulching as ‘volcano’ mulching. It is ok to apply mulch a few inches thick as long as the mulch is left 4 to 6 inches away from the base of the plant. This method is shown in the photo on the right.

Proper mulching is a tremendous benefit to plants. It involves using 3 to 4 inches of a good organic product such as wood chips or shredded bark. These products break down over time, supplying trees and shrubs with added nutrients. Mulch also helps to retain soil moisture, create a protected environment for the root zone during the winter, and protect trunks from lawnmower and weed wacker damage.

We call the improper method ‘pyramid’ mulching. This destructive method of pyramid mulching is shown in the photo on the right and should never be used! If mulch is applied improperly, it quite often results in the death of trees and shrubs!

You have probably seen neighboring properties which mulch piled up onto the trunks of trees. It is important to realize that even 2 inches of mulch touching the base of a tree or shrub may prove to be too much. When mulch is allowed to come into contact with the base of trees or shrubs, it traps moisture against bark. It causes the bark to become soft and spongy and allows Borers (insects which burrow into the bark and live beneath it) easier access. The Borers then feed and tunnel under the bark, and once they girdle the tree, it dies.

  • Our landscaper piled the mulch onto the trunks of our trees. We assumed that they knew what they were doing. Is this correct?

     It never fails to amaze us that some in our industry don’t know the basic do’s and don’ts of their own business. Keep in mind that your landscaper works for you! Explain what is expected and make sure that they mulch properly.
  • We’ve piled mulch up against our tree trunks for years. Why haven’t we lost any trees yet?

    We are not saying you will definitely lose a tree due to improper mulching practices. What we are saying is that this practice greatly increases the chances that a tree might die at some point in the future if this type of mulching is practiced consistently.


    In 2011, a client of 15 years called saying that his pride and joy 30-inch diameter Sugar Maple (which he transported and planted 40 years earlier from his grandparents’ farm and that shaded the entire back of his house and deck) looked really sick all of a sudden.

    Upon inspection, we pulled the mulch off the trunk (which we had warned the homeowner about several times over the years). We were able to grab the loose, rotting bark by hand and pull it off the tree with little effort. Beneath the bark, all types of different insects were scurrying about. This gorgeous, coveted tree was now dead.


CAUTION: Sprinkling Systems May Do More Harm Than Good!

“Established” trees and shrubs should ideally receive 2 inches of water every 10-14 days if no rain has fallen. Newly planted trees and shrubs should get thoroughly soaked once every 7 days during their first year in the ground.

Also, always soak all trees and shrubs thoroughly just prior to the winter ground freeze, even if it means watering in late November. This is especially true of plants like Euonymus, Boxwoods, Rhododendron and Conifers (Pines), or any plant that holds its leaves or needles all winter long.

  • How do I water properly and know when I’ve achieved the recommended 2 inches in the area that I am watering?
    It is best to water with a traditional sprinkler. A sprinkler best duplicates rainfall, depositing water to all areas where roots may be present. To judge 2 inches of water, place a rain gauge in the yard in the area that is to be watered. (Make sure that excess water dripping from limbs or leaves above the gauge is not an issue, as that will fill up the gauge much sooner and throw off the reading). Note the time it takes to achieve the 2 inches with that particular sprinkler.
  • Is it OK to water with a probe?
    Most of us have seen it. A hose attached to a probe stuck a few feet into the ground to get those ‘really deep roots’. This practice is a total waste of good water since 90% of a trees ‘feeder’ roots are located in the top 8-10 inches of soil. And, this is true even for the biggest 300 year old Oak trees. ‘Structural’ roots go deeper than that, but they won’t absorb enough water to help the tree. Roots train themselves to stay shallow to take advantage of the ‘light’ rainfalls, which are the norm, versus the more rare, deep soaking rains we receive. Pushing the probe 2 feet into the ground misses the feeder roots, covers too small of an area, and requires too much supervision as the probe needs to be moved constantly. In addition, it is often easy to forget that the hose is running as we get distracted during the day.
  • I have an automatic watering system on a timer. Shouldn’t my plants be getting plenty of water?
    Watering systems on timers are actually more of a problem! These systems are too convenient for their own good. We can’t tell you how many sick trees we are called out to inspect that are dying due to too much water from watering systems that activate on a timer. Even 10-20 minutes per zone every 2-3 days is too much! When we dig up the roots, we find they are black, slimy and have no fine root hairs for water absorption capability.


    This type of frequent watering is great for the grass but deadly for most trees and shrubs. When the ground is wet this often, crucial oxygen cannot penetrate the soil. If the roots don’t get an opportunity to dry out on a regular basis and obtain oxygen, trees and shrubs develop ‘wet feet’ and roots begin to rot away. Again, use the rain gauge to determine how long it takes to put down 2 inches of water. If a homeowner plans on having the greenest lawn in the neighborhood, their trees and shrubs will unfortunately suffer.

    Tree Green recommends disregarding the automatic timer on the watering system. You can enjoy the convenience of a watering system from the standpoint that you don’t need to drag a hose around, but only activate the zones on an as-needed basis as outlined above

What causes Winter Burn?
Winter Burn results when air temperatures rise for short periods of time over the winter and plants begin creating food and energy from within, through the process of photosynthesis. In doing so they release large amounts of water through their leaves and/or needles as they warm, but since the ground and roots remain frozen, and roots cannot absorb water when frozen, the plant cannot replenish the lost moisture which results in browning.

What can you do about it?
If you notice browning on any of your trees or shrubs, what can you do now? Water thoroughly, as soon as the ground thaws. Many home owners mistakenly think that melting snow adds substantial soil moisture in springtime, helping their trees and shrubs.

This is unfortunately not true. Why? Obviously the ground is frozen all winter long so melting snow runs off into the sewers, rivers and lakes before the ground can thaw enough for much absorption to take place. Therefore, as soon as the ground does thaw, if we do not receive normal amounts of spring rain soon thereafter, water your plants at that time. Doing so will limit some of the Winter Burn damage that has yet to appear.

When should you water?
How can you tell if the ground is ready to absorb water? Step a shovel into the ground. If it easily penetrates at least 6 to 8 inches, it’s time to water.

Will Winter Burn Kill Plants?

In some instances, yes. But don’t be hasty in removing plants. Wait to see if new growth emerges this spring and into the summer. If new growth does emerge, much of the damaged foliage will fall from the plant over the summer and the new growth will fill out and rejuvenate the plant over time.

Proper watering, in combination with high quality root fertilization, will go a long way in helping your trees and shrubs to recover.

Experience the Tree Green Difference

At Tree Green, we don’t just care for trees; we care for people. Our approach melds hassle-free scheduling with prompt response times, so you can rest assured your time—and your trees—are highly valued. But what truly sets us apart is our blend of 1950s-style customer service with modern arboricultural expertise; it’s where time-honored values meet cutting-edge science.

We’re fully committed to exceeding your expectations at every step. Our certified arborists not only offer you the best tree care solutions but also extend the utmost respect to your property. In a world where customer service often falls by the wayside, we’re raising the bar, one satisfied customer and healthy tree at a time.