Page 6 Prince George Real Estate_________  September 7, 2000
Fall Garden Pests and Diseases
By Lois Hole
  (LH)-At this time of year, people are thinking more about what to cook for Thanksgiving dinner than their gardens. However, there are still a few odds and ends to take care of in the yard. Heading off diseases and insects is one of those tasks, and in my experience the best way to discourage these pests is to clean up your garden before the snow falls. Knowing a little about how diseases and insects behave helps, too.
Diseases
  It would be nice if there were some magic spray or secret method of getting rid of all diseases. Of course, there's no such thing. Fortunately, removing dead, diseased or decaying tissue as it appears can go a long way towards preventing the spread of future diseases. Most diseases go through a cycle. First, they infect the plant. Then, when winter arrives, they go dormant and wait inside the infected tissue. When spring arrives, the diseases leap back to life and reinfect the plant. So, removing diseased branches and stems in the fall greatly reduces the possibility of reinfection next year. Diseased tissue isn't always easy to spot, but do the best you can-get rid of tissue with obvious cankers, holes, or black, dead patches. Remember to cut if off with clean, sharp pruners to prevent undue damage to your plants, and never throw diseased tissue into the compost pile.
  Cutting down rose canes is another good way to forestall disease. Some people like to leave the canes in place to trap snow, which helps tender roses over winter, but I prefer to remove canes and use mulches like peat moss for insulation. It's much easier to remove the mulch in the spring than to have to deal with diseases (and insects) harboured by
uncut canes. It's especially important to cut back and clean up canes when the plant has a history of problems. Hybrid teas should be cut down to about 15-30 cm from the soil; hardy roses, generally more resistant to disease than hybrid teas, should just be trimmed to shape if you desire.
  Any part of a plant may provide shelter for disease. That's why you should never keep potato tubers over the winter for planting next spring-these can harbour serious diseases like bacterial ring rot, which causes a horrid, mushy brown ring to appear in tubers. Certified seed potatoes are free of such diseases; it's far better to buy these each year than to risk spreading this disease in your garden.
  Speaking of tubers and the like, never store any soft and mushy corms, bulbs, or ornamental tubers.
These will continue to deteriorate in storage and spread disease to healthy tubers.
Insects
  The shorter, cooler days of September are triggering certain insect behaviors. Most importantly, hibernating insects are on the lookout for hiding places. They'll take shelter in cracks and bark on trees, in leaf debris, and any other sheltered spots they can find. Once more, your best strategy for preventing an insect resurgence in the spring is to remove any dead, dying or insect ridden branches, especially since most sprays are useless in the fall.
  One exception is a product called dormant oil. Dormant oil is a horticultural oil that coats and suffocates insects. It should be sprayed on trunks, branches and canes after the leaves have either fallen or been cleaned off. The oil kills mites and aphid eggs and can also kill some hibernating diseases. Another good spray is a special lime-sulphur concoction. It kills mites and disease, but should only be used on dormant plants. The lime-sulphur combination can cause severe burning on foliage, but once all the leaves have fallen in September or October, there is no risk of damage.
The Last Word
  This isn’t a time to rest on our laurels-our tiny enemies certainly aren't about to head into fall without having a plan for spring in mind. So hold off on those Thanksgiving preparations until you've frustrated their ambitions.
  For further information contact Hole's, 101 Bellerose Drive, St. Albert, Alta or their Website at www.holesonline.com.