Winter is the ideal time to prune most shrubs and trees
Correct pruning is a landscape practice that can enhance the health, vigor and aesthetics of your trees and shrubs. In this blog, we are discussing five advantages to pruning in the winter:
1. During the winter, most woody plants are dormant and so are the many diseases and insects that can potentially invade pruning cuts. When a plant is pruned during the growing season, for many plants, the activity of pruning during the growing season actually signals the plant to grow. Winter pruning when the plants are dormant, enable you to prune deeper without the plant trying to grow.
2. After leaves have fallen, it is much easier to see the plants overall form and structure. Damaged and diseased branches are more readily apparent when not obscured by foliage.
3. Pruning in the late summer or early fall can stimulate new growth that may not harden off before the cold weather. This is not a concern during the winter. (As discussed above)
4. Winter pruning is good for your plants, leaving them with extra root and energy reserves to quickly heal wounds and support vigorous spring growth that will obscure the pruning cuts.
5. Winter pruning is also good for you, giving you a reason to go outside on a mild winter day to enjoy your landscape.
Although winter and early spring is a great time to prune, if the tree or shrub is a spring flowering plant and the blooms are important to you, it may be best to wait and prune that plant shortly after it is done blooming. Even though pruning spring blooming plants in the winter will never adversely affect the plant’s health, it can reduce those blooms. [Read more…]
We all liked to jump into large piles of leaves as children. However, now that we are homeowners we have the added responsibility of keeping our yards in check. Each fall, mother nature covers our lawn with leaves and there are a number of ways to deal with those fallen leaves.
Turn Those Leaves into Mulch…
Many lawn mowers have a mulching option whereas the mower can chop the leaves into much smaller pieces and most of the leaf matter will disappear into the turf. Mulched leaves are a great natural way to feed your lawn provided the leaves are not too thick and choking out the turf by disrupting light, water and nutrients from getting into your lawn. Many homeowners also use the mulched leaves around their plants to help feed and protect shrubs, etc. But, be aware that many types of leaves are high in acid and may not be that beneficial.
Remove the Leaves
As mentioned, your lawn needs light, water and nutrients to survive and hopefully thrive. If there is a blanket of leaves on your lawn, it is likely that your turf is missing the benefits of light, moisture and any nutrients available. Lawns can show these signs of stress by developing brown spots, bare spots and grass blades that are more yellow than green. It is important to remove any leaves that come from trees with insect infestations or diseases. Leaves that are infected by insects and disease can ultimately create more problems down the road if they are allowed to stay on the turf.
Some of the more common issues that leaves left on your lawn could cause are brown patch and snow mold. In addition, the leaves left on the lawn will likely slow down or eliminate germination of new grass in the late winter and early spring making the appearance of your lawn less than desirable for the summer months.
Leaves Rain on the Parade of Cool-Season Grasses
Most lawns in Virginia are made up of one or more cool-season grasses. “Cool-season grasses” are so called because they are most active during those periods of the year when the weather is moderately cool. Fall is one of those times. Blessed with enough sunlight, nutrients and water, and enjoying temperatures that are neither too cold nor too hot, cool-season grasses such as a high-quality Fescue or Kentucky bluegrass revitalize themselves in the fall. This is when they must “make hay,” strengthening their root systems and that is why fall is the ideal time to aerate and overseed cool-season lawns.
But a thick layer of fallen leaves can get in the way of the growth of these grasses. Why? Because, for one thing, the leaves can deprive the grass of one of the key elements just mentioned: sunlight. If not raked up or removed in a timely fashion, a thick and/or matted layer of fallen leaves casts too much shade over the grass below.
Most disease-free leaves that can be finely mulched ultimately create a great nutrient base (in time, becoming compost) for your lawn and plants. However, for the long-term benefit of your lawn, mulching or removing these leaves will help your lawn year around.
Benefits of Proper Mulching
Good tree maintenance is common sense – it is what trees need to flourish in nature. In the wild, the forest floor is naturally covered with a layer of decomposing leaves, twigs and other plant material. In urban settings, the most common mulch is made of wood chips of varying types and sizes.
Properly Applied Mulch:
· Impedes growth of weeds and grass that compete with tree roots robbing them of water and nutrients.
· Conserves soil moisture by slowing down the evaporation of water from the soil surface helping to retain more water for root use for longer periods of time.
· Protects the trunk from mower/ weed whacker damage by eliminating the need to mow or trim immediately around the trunk.
· Reduces soil compaction by reducing foot and vehicle traffic allowing roots to breathe.
· Moderates soil temperature keeping the roots cool in the summer and warm in the winter there-by reducing stress.
· Improves soil fertility as it decomposes.
· Prevents erosion.
Mulch Out, Not Up
· No mulch volcanos. Mulch should not be deeper than 2-4 inches. If using finely textured or double shredded mulch, use 1-2 inches because these materials allow less oxygen to the root zone.
· Not against the trunk – keep all mulch 3-4 inches away from the trunk of the tree or shrub, allowing the root flare zone to show just above ground level.
· Spread the mulch out to the tree’s drip line if possible. Remember that the drip line moves out as the tree grows. (see “How Roots Really Work” drawing.)
· Other Tips:
If a “fresh” look is desired each season, take some of the old mulch away before adding a new layer to reach the 2-4” depth. Just lightly raking the existing mulch can achieve a finished look. Applying new material over old in successive years is the same as applying a too deep layer all at once!
Remember: Keep the bark dry and the roots moist.
Problems Associated With Over-Mulching or Incorrect Mulching
Incorrect mulching is a waste of time and money and is quickly becoming the number one cause of death of trees and shrubs. Over-mulching, with mulch piled high, directly against the stems or trunks, smothering the root flare zone; or with very deep mulch covering part or all of the root area cause:
— Root Suffocation/ Root Rot – Repeated or deep applications of mulch cause waterlogged soil by slowing water loss through evaporation. Roots must “breathe”, taking in oxygen. When oxygen levels drop, root growth declines then they die, making it impossible for the plant to take up water and nutrients, leading to death.
— Inner Bark Death – The living tissue (phloem) just inside the outer bark must be able to freely exchange oxygen and carbon dioxide. Mulch piled high onto the trunk decreases gas exchange, killing the inner bark and then the roots, which can no longer receive food from the leaves.
— Rodent/ Insect Chewing – Deep layers of mulch against the trunk provide a perfect habitat for these pests. If chewing is extensive (more than 50% of the circumference) or “girdles” the entire tree, little can be done to save the tree.
— Fungal and Bacterial Diseases – These can grow and reproduce in the thick, moist mulch next to the trunk, gaining entry into the stressed, decaying bark. Once established, cankers caused by these diseases, can encircle the tree, killing the inner bark, starving the roots and killing the plant.
— Excessive Heat – Thick layers of mulch begin to decay and can produce heat (similar to composting).
Waterproof Layers – Thick layers of certain mulches can create impervious surfaces that do not allow water to reach to roots, especially during drought. Roots dehydrate and die, killing the tree.
Symptoms of Decline
Death from over-mulching is gradual, with symptoms sometimes taking 3-5 years to express themselves. It starts with the decline of plant vigor and rate of growth.
· Off-color leaves (pale or marbled)
· Abnormally small leaves
· Poor twig growth
· Die-back of older branches
· Rotting, pealing trunk bark under the mulch are classic signs that get worse every year, and at the point they are recognized, it is too late to apply corrective measures.
Dos Amigos will care for your trees from planting and installation to mulching and pruning for healthy growth. Dos Amigos has more than 40 years of experience pruning and caring for trees and shrubs.
Soucres: Chris Carlson, Dir. Hort. Tech., Kent State U.; Diane Relf, Environmen. Hort. VA Coop Ext, VA Tech; Dr. Robt. Nuss, Hort. Penn State U.; Donald Rakow, Cornell Univ. Drawings from International Society of Arboriculture Training Manual or drawn by Barbara Lupfer, Certified Arborist..
Compiled and edited by Barbara Lupfer, Certified Arborist
Winter is the ideal time to prune trees and shrubs. The type of pruning depends on what each tree needs. Here are the basic types of pruning that we perform.
CLEANING is the removal of dead, dying, diseased, crowded, weakly attached, and low-vigor branches from the crown of a tree.
THINNING is the selective removal of branches to increase light penetration and air movement through the crown. Thinning opens the foliage of a tree, reduces weight on heavy limbs, and helps retain the tree’s natural shape.
RAISING removes the lower branches from a tree in order to provide clearance for buildings, vehicles, pedestrians, and vistas.
REDUCTION reduces the size of a tree, often for clearance for utility lines. Reducing the height or spread of a tree is best accomplished by pruning back the leaders and branch terminals to lateral branches that are large enough to assume the terminal roles (at least one-third the diameter of the cut stem). Compared to topping, reduction helps maintain the form and structural integrity of the tree. Advantages of thinning include better air circulation, improved sunlight penetration, and less wind resistance.