How to Control Sapstreak Disease of Sugar Maple

/Home/Garden Basics/Trees/Tree Diseases/Maple Tree Diseases/Maple Tree Sapstreak Disease

Sapstreak disease, caused by the fungus Ceratocystis coerulescens, is a serious threat to sugar maple forests. Although the disease is causing only minor damage at present, it has the potential to become an important problem. Sapstreak is a fatal disease; infected trees do not recover. In addition, timber salvage value is low because the wood is discolored.

Sapstreak has been reported in isolated areas of North Carolina, Michigan, Wisconsin, and Vermont. Only sugar maple is affected. At present the best sapstreak control method is prompt removal of newly discovered infected trees to prevent spread to nearby healthy trees. The disease is spread by insect disseminated-ascospores and endoconidia that infect trees through root and basal trunk wounds.

Symptoms
Look For: Dwarfing of leaves and crown dieback
Look For: Dwarfing of leaves and crown dieback. The first noticeable symptom of sapstreak is a dwarfing of the foliage on all or a portion of the crown. In following years, the dwarfing becomes more pronounced, spreads to previously unaffected parts of the crown, and parts of the crown die. Generally after 3 to 4 years the entire tree dies.

During this time, the wood of the lower stem and root system becomes stained in a characteristically radiating pattern.
Look For:Water-soaked gray to brown radiating patterns. On freshly cut trees, tips of the streaks nearest the bark may be green or red. Look For: Water-soaked gray to brown radiating patterns. On freshly cut trees, tips of the streaks nearest the bark may be green or red. Sapstreak pattern on stump. Sapstreak pattern on stump.

Sporulation of sapstreak fungus on the end of a log which had been left lying in the woods for a few summer days. Sporulation of sapstreak fungus on the end of a log which had been left lying in the woods for a few summer days.
Fruiting Structures and Spores
Look For: Two kinds of fruiting structures on freshly cut logs and stumps.
Ascospore stage -long-necked black erithecia with ases bearing long, slender, dark, thinwalled hyphae. (100X) Ascospore stage—-long-necked black perithecia with bases bearing long, slender, dark, thin-walled hyphae. (100X) Conidial stage — endoconidiosphores (a) which extrude barrel-to oval-shaped hyaline endoconidia (b). (20OX) Conidial stage — endoconidiosphores (a) which extrude barrel-to oval-shaped hyaline endoconidia (b). (200X)
Culturing
Check the culture for dark rapid growth, production of endoConidia, and a characteristic musty, sweet odor. To isolate the fungus asceptically split open a block of streaked wood and carefully remove chips with chisel and forceps. Plate the chips on almost any medium recommended for routine growth of fungi, such as potato-dextrose agar, and incubate at 20 to 25 C in the light. Another isolation procedure is to incubate pieces of streaked wood in moist chambers at room temperature until the perithecial stage of the fungus develops on the wood. After a few days, masses of ascospores will accumulate at the tips of the perithecial necks. These spores can then be picked up with a sterile dissecting needle and transferred to an agar plate.

Check the culture for dark rapid growth, production of endoconidia, and a characteristic musty, sweet odor.
Control
bullet point Losses can be minimized by preventing or eliminating entry points for the disease.
bullet point Avoid wounding maple trunks and roots during logging.
bullet point Apply a wound dressing to any wounds that do occur.
bullet point Remove diseased logs promptly.

Author:
Kenneth J. Kessler, Jr.
Principal Plant Pathologist
North Central Research Station
St. Paul, Minnesota
Copies available from:
North Central Research Station
1992 Folwell Avenue
St. Paul, MN 55108


1978
U.S. GOVERNMENT PRINTING OFFICE: 1980-766-370
Pesticides used improperly can be injurious to human beings, animals, and plants. Follow the directions and heed all precautions on labels. Store pesticides in original containers under lock and key out of the reach of children and animals and away from food and feed.

Apply pesticides so that they do not endanger humans, livestock, crops, beneficial insects, fish, and wildlife. Do not apply pesticides where there is danger of drift when honey bees or other pollinating insects are visiting plants, or in ways that may contaminate water or leave illegal residues.

Avoid prolonged inhalation of pesticide sprays or dusts, wear protective clothing and equipment, if specified on the label.

If your hands become contaminated with a pesticide, do not eat or drink until you have washed. In case a pesticide is swallowed or gets in the eyes, follow the first aid treatment given on the label, and get prompt medical attention. If a pesticide is spilled on your skin or clothing remove clothing immediately and wash skin thoroughly.
NOTE: Some States have restrictions on the use of certain pesticides. Check your State and local regulations. Also, because registrations of pesticides are under constant review by the U.S. Environmental Protection Agency, consult your local forest pathologist, county agriculture agent, or State extension specialist to be sure the intended use is still registered.

Contact Information

USDA Forest Service
Northeastern Area
Office of the Director
11 Campus Blvd., Ste 200
Newtown Square, PA 19073

Phone (610) 557-4103
TDD (610) 557-4160