9 LATE-SEASON LANDSCAPING TIPS

Tree & shrub spraying

1. Schedule pruning to promote good canopy structure and prepare trees for winter storms. This especially applies if you have oak or elm trees.

2. Aerate your lawn to reduce soil compaction, allow nutrients a better path into the soil and improve the root density of your turf.

3. Schedule dormant oil treatment to reduce overwintering insect populations.

4. Use hardware cloth or fencing to protect susceptible trees or shrubs from rabbit or mice damage over the winter.

5. Schedule a deep-root fertilization or soil amendment treatments to optimize fall root growth and development.

6. Give your evergreen plants one last deep watering before putting the garden hose away for the winter.

7. Schedule an anti-desiccant treatment to reduce moisture loss from evergreen trees and shrubs over the harsh winter months.

8. Burlap any plants that could suffer from salt spray, strong winds or deer feeding over the winter.

9. Remove any large accumulations of leaves that could cause turf dieback over the winter.

Oak tree pruning

CRABAPPLES LOSING LEAVES?

A common ornamental tree disease arborist’s encounter in Michigan is apple scab. This foliar disease infects crabapple leaves in the spring, but does not make itself apparent until later in the summer. After the apple scab fungus has infected enough of the crabapple leaf the leaf will fall from the tree.

Crabapple trees infected with apple scab usually start to show the effects of the disease between mid-June and early July. By August some crabapple trees may have even lost most of their leaves.

If your crabapple tree has lost a lot of its leaves from apple scab it is really not worth spraying the tree with a fungicide at this time. The disease is already in the leaf tissue and further apple scab infection is not going to be significant in the warmer and drier months of the year. Make sure the tree is receiving ample water and you may want to consider fertilizing in the fall to assure adequate nutrients are available to the tree.

The best way to prevent apple scab in the future is to apply a foliar fungicide spray in the early spring. Crabapple spraying for apple scab should start soon after the leaves begin to emerge. A couple follow up treatments will give you the best level of control.

To learn more about controlling apple scab click here:
http://www.owentree.com/Apple_Scab.php

Apple scab infection

 

WHY IS MY PINE TREE BROWN?

Shortly after summer temperatures become the norm pine trees affected by pine wilt start to turn brown. 

Scots pine killed by pine wilt. Photo: USDA Forest Service - 

North Central Research Station , USDA Forest Service, Bugwood.org 

Pine wilt is a disease of pine trees caused by Pinewood nematodes, a microscopic roundworm. Though all species of pines found east of the Rocky Mountains in the United States are hosts, Pinewood nematode is most commonly found on Scotch pine. Native pine tree species are resistant, with the nematodes being more of a problem on introduced species of pines.

Most often the first sign of pine wilt is the sudden decline and death of an entire pine tree, usually from the warmest part of the summer through the fall. The dead tree could retain its needles for as long as one year. Because the dead wood is dry it becomes very brittle.

Pinewood nematode is transmitted from tree to tree by pine sawyer beetles which overwinter as larvae in dead pines or pine logs which still have the bark attached. After pupating, the adult pine sawyer beetles, carrying nematodes in their tracheae, fly to healthy host pine trees where the nematodes enter through feeding wounds. Pinewood nematodes migrate to resin canals where they feed and rapidly reproduce. The resin canal system is damaged and water movement in the tree is disrupted. Once the pine tree dies the nematodes continue to feed and reproduce on blue stain fungus which infects the tree. In summer, female pine sawyer beetles carry nematodes as they fly back to dead pine wood where they lay their eggs. Eggs hatch and the larvae and nematodes overwinter together after which the cycle starts again. 

Pine sawyer beetles vector the nematodes that cause pine wilt. 

Photo: L.D. Dwinell, USDA Forest Service, Bugwood.org 

 Because decline and death of a pine tree infested with Pinewood nematode occurs very quickly, it is usually too late to save a single tree. If there is a group of pine trees on the site insecticide treatments can be done in an effort to save the remaining trees. Dead branches should be pruned from live trees to reduce the attraction of pine sawyer beetles. Any dead pine trees or firewood should be removed or destroyed. Do not use the mulch from an infested tree for mulch. When replacing dead trees choose species which are immune to pine wilt such as Norway or Colorado blue spruce, Douglas-fir, cedar, hemlock or white pine trees.

The International Society of Arboriculture certified arborists at Owen Tree Service are experts at recognizing pine wilt in both young and mature trees. If your think your browning pine tree might have pine wilt give our arborists a call. Our company was founded on tree and shrub care services. 

Blue stain fungus on pine logs. 

Photo: L.D. Dwinell, USDA Forest Service, Bugwood.org

 In addition to pest control services our experienced tree crews perform pruning trees or trimming shrubs and tree removal. Professional tree care services do not do topping of trees because of the harm it causes. Owen Tree Service can make trees smaller by proper crown reduction pruning.

Owen Tree Service provides lawn fertilization and weed control, in addition to insect and disease control for trees. We also have landscaping crews that can plant new trees or shrubs for you or apply organic mulch to freshen up your shrub beds.

GROUND COVER DISEASES

Three common ground covers used in Michigan are pachysandra, vinca/myrtle, and English ivy. Although mostly problem-free, on occasion they can be subject to disease problems. In most instances of diseases on ground covers a fungicide program in combination with good cultural practices can eliminate the problem.

 Pachysandra ground cover. 

Photo: Jil Swearingen, USDI National Park Service, Bugwood.org 

 Pachysandra. Volutella leaf and stem blight is the most common disease on pachysandra. The disease is usually promoted by excessive moisture for long periods of time. The fungus causes black blotches on the leaves and black cankers on the stem. To control Volutella leaf blight, avoid excess moisture from overhead irrigation. A fungicide spray program started in the spring can usually prevent the disease from spreading.

 Volutella blight on pachysandra ground cover plants. 

Photo: Mary Ann Hansen, Virginia Polytechnic Institute and State University, Bugwood.org 

 Vinca (periwinkle) ground cover. 

Photo: Jil Swearingen, USDI National Park Service, Bugwood.org 

 Vinca/Myrtle. Phoma stem blight is the most common disease of Vinca in Michigan. The fungus generally rots and girdles lower stems. Often the first symptom noticed by homeowners are wilted leaves as a result of girdled stems. Like Pachysandra, Vinca diseases will be minimized to some extent by avoiding excessive moisture, particularly in shaded areas of the landscape. Excess fertilization will also cause lush dense growth and greater susceptibility to the disease. Fungicide sprays will usually eliminate this ground cover disease over time.

 Phoma stem blight. 

Photo: Howard F. Schwartz, Colorado State University, Bugwood.org 

 English ivy. 

Photo: Jan Samanek, Phytosanitary Administration, Bugwood.org 

 English Ivy. Several fungal leaf spots and a severe Xanthomonas bacterial leaf spot are possible causes for brown or black spots on English ivy. Although bacterial leaf spot often has a yellow halo surrounding the dark lesion on leaves, the fungal and bacterial disease can appear similar. Moisture control is particularly important for the bacterial leaf spot. Fungicides may actually spread the bacterial disease but may inhibit the fungal leaf spots. A lab test may be warranted to confirm which disorder is affecting the plants. Where practical, infected leaves may be picked and destroyed.

 English ivy with bacterial leaf spot. 

Photo: Leslie J. Mehrhoff, University of Connecticut, Bugwood.org