Welcome to Pest Alert. Categories for topics are as follows, H - Herbaceous plants and flowers, W - Woody Plants, V - Vegetables, F - Fruit and L - Lawns.
DISEASES
V,H SANITATION, SANITATION & SANITATION are the three keys to managing diseases for next season. Carefully clean up the leaves and other plant debris from the garden this fall, especially if the plants suffered any disease problems. Many foliar diseases overwinter on diseased plant debris from the previous season so removing this material reduces future problems. If you don't physically remove the material, plowing it under will work well too. However, rototilling the garden will only bury some of the debris and leave much of it at or near the soil surface where it can start disease problems for next season. Organic waste from the garden makes excellent material to add to the compost pile. And, as long as the pile is active, the material will be safe to incorporate back into the garden next season as compost. For additional information on composting see ExEx 6004 - Composting Yard Waste and ExEx 6005 - Recycling Lawn and Yard Waste.
INSECTS
W THE PINE ENGRAVER BEETLE (Ips pini) is causing losses in recently planted pines throughout the Black Hills. In some instances the trees were moved last fall but died this summer despite pesticide applications made this spring. Unfortunately, it appears that trees moved from native stands in the fall may have been recently infested by the last generation of Ips (last flight occurs in September). The infested trees usually remain green until the next spring or summer but they generally die before they candle out. Pesticide applications made after the beetles have attacked the tree are ineffective. If trees are moved in the fall from native stands, as opposed to nurseries, they should be inspected for recent borer attacks. Remove a small portion of the bark along the stem and check for galleries (tunnels) and the presence of the beetle. Usually even the removal of a small patch of bark with a knife will reveal any activity.
WEED CONTROL
L,V,H LATE FALL WEED IDEAS. 1) Perennials like quackgrass and field bindweed in the garden area can be treated with Roundup. Wait at least a week before tilling. 2) Dandelion can be treated very late. It doesn't freeze easily. Recent rain will trigger more seedlings if it warms. 3) Use Roundup to treat grass and weeds if you are starting a new garden area for next year. 4) Burning weeds that have been raked into a pile in the garden likely has only limited weed control value. Most seeds have shattered and spread before they were moved into the pile and are not affected by the fire. 5) Check chemical storage. Glass bottles break if they freeze. Clean hand sprayers with ammonia and soap. Don't store them in a manner that hoses are bent or kinked. 6) Perennial grass is not damaged by early freezes. Roundup can be applied as a "border" barrier to keep grasses from encroaching into gardens, asparagus patches, in gravel drives, around posts or trees, or in rock borders. This can often be doe in late October. 7) Don't try to use Roundup to take out invading grass in raspberries. The new shoots will translocate the chemical into other plants in the patch. 8) Retreat groundivy with broadleaf spray herbicides (such as 2,4-D, MCPP, diacamba, mixes). Two applications in fall are usually required. The weed grows after temperatures drop into the 20's.
OTHER NOTES
W FALL NEEDLE DROP. At this time of year evergreens from arborvitaes to spruce begin shedding some of their older needles or scales. Pines typically loss their three year old needles, while spruce and fir their fifth to eight year old needles. In all instances it is their oldest needles so the shedding occurs in the interior of the tree, not the needles at the tips. Junipers and arborvitaes also loss their oldest needles or scales but these appear more scattered through the canopy rather than strictly in the interior.
W PREPARE FOR RABBIT AND DEER DAMAGE. Some of the products on the market to reduce the problem with their feeding and rubbing have active ingredients of thiram, fermented egg solids or ammonium salts of fatty acids. These should be applied in the fall and may have to be reapplied during the January thaw to provide protection through March. Applying a spray made of 1 part thiram, 2 parts white latex paint and 8 parts water will usually provide protection for the entire winter. The paint acts as a sticker and also lets you know where you sprayed. It weathers off by April.
W PROBLEMS WITH PEOPLE WANTING TO MAKE "FREE" CHRISTMAS TREES of your ornamental planting can be stopped by treating the trees with a spray that is 1 part glycerine, 2 parts fox urine (you can buy this commercially, you don't have to catch the fox!) and 10 parts water. The spray does not smell while it is cold outside, but cut the tree and bring it in the house and the odor becomes very apparent. Obviously, the only way this works is have notices out that the treatment has been performed. The spray wears off by the end of winter.
L TIRED OF RAKING LEAVES? Fallen tree leaves can be recycled into your lawn with several passes using a mulching mower or regular rotary mower with the side discharge unit blocked. Recent studies have shown that mulching of leaves is not detrimental to the turf, and may provide a number of benefits, including increased microbial activity, water infiltration, and improved soil structure. Additionally, nutrients are recycled back into the turf profile. Application of 1 lb. of nitrogen per 1000 ft2 in late fall will help to adjust the temporary change in the carbon:nitrogen ratio due to the introduction of leaf residue.
W TREES SHOULD BE FERTILIZED AT THIS TIME. Nutrients absorbed now, while the soils are still warm and moist, are stored and made available for next year's growth. In fact studies have indicated that nutrients applied in the fall are used for spring growth more than nutrients applied in the spring. Fertilizers applied at this time will not reduce winter-hardiness or increase winter injury.
Back to the Pest Alert page
Most recent revision Thursday, Oct. 8, 1998 by David F. Graper.