| Fungi: |
|
Fungal diseases
are rare in Montana lawns because our climate is dry. They are
spread by spores,
which can be carried by wind and water.The best way
of handling fungal problems is usually through prevention (removing
and/or destroying diseased plant litter), refraining from over
watering,
and aeration at least once per year.
|
|
Condition/Control
|
Cause
|
Clemson
University - USDA Cooperative
Extension Slide Series,www.ipmimages.org |
Condition: Dark
green circular area more vigorous in growth with or without mushrooms
bordered by a dead zone.
Control: Top dress ring with organic residues
(finished compost). Fertilize and water area well.
Encourage water percolation by plunging a garden fork into the
soil five or six inches deep around the ring and watering
well. Remove mushrooms and soil below, replace soil with
finished compost. |
Fairy Ring
(Basidiomycetes) |
Missoula
County Extension Service
|
Condition:Yellow lower
leaves with reddish black round spots.
Control:
Prune woody plants to allow more sunlight to lawn.
Avoid excessive irrigation or fertiliztion.
|
Melting Out
(Drechslera
spp.)
|
Missoula County Extension Service
|
Condition:White
dust on grass blades; may eventually cover the entire blade, can cause
yellowing and puckering
Most often found in shady wet areas.
Controls: Avoid excessive irrigation, especially at night, evening, or early morning. (See link at right).
|
Powdery Mildew
(Erysiphe, Sphaerotheca, Phyllactinia,
Microsphaera,
Podosphaera,
or Uncinula spp.)
|
Missoula
County Extension Service
|
Condition:Pinkish - red strands form at leaf tip in spring and fall on red
fescues and Kentucky bluegrass.
Controls:
Prominent on nitrogen-deficient lawns
Use a balanced fertilizer
Water to reduce drought stress between 10 am and 2pm.
Collect grass clippings to reduce spread.
|
Red Thread
(Laetisaria
fuciformis) |
Missoula County Extension Service
|
Condition: Irregular,
circular white to gray or pink spots on lawn. Visible when snow
and ice
recede.
Controls: Avoid
traffic on frozen turf, add compost to lawn in fall, mow
lawn to less than 2 inches before freezing in fall, aerate the lawn,
rake out and reseed dead
patches in Fall or Spring.
|
Snow
Mold
(Fusarium patch) |
Missoula
County Extension Service
|
Condition: Winter
watering may not be necessary for established lawns. However, lawns
started within the last year may be susceptible to winter
desiccation injury and need supplemental winter irrigation.
Control: Water
only when air and soil temperatures are above 40 degrees F with no snow
cover. |
Winter Desiccation |
|
| Insect troubles: |
|
Good cultural
practices are essential to prevent insect pests from destroying turf.
Use recommended methods of fertilization, watering, mowing, etc., to
keep grass healthy and growing vigorously. A healthy lawn can tolerate
light insect infestation and damage is masked or overcome by rapid
growth of plants.
|
|
Condition
|
Cause
|
Whitney
Cranshaw, Colorado State University, www.ipmimages.org
|
Young leaf
blades cut off at soil line,
brown spots in lawn.
Control: Neem
(Turplex), Granular forms of Bt (Bacillus
thuringiensis) misxed with bran applied in the evening.
|
Cutworms |
M.G. Klein, USDA, www.ipmimages.org
|
Weak turf, death in large patches
Root pruning
Damage seen in late summer
Controls:
Beneficial nematodes, Mycongen. Bt (Bacillus thuringiensis - variety: japonensis builbui or "M-Press"
|
White
Grubs |
|
