Symptom: Plants appear dusty or dirty and fail to grow well. Leaves may take on a yellowing between the veins. Small amounts of silken webbing may be present on new growth and on the undersides of leaves. If a white piece of paper is held under foliage and the plant is batted, small specks will fall onto the sheet and begin to move about. Cause: Spider mites are the cause. These tiny insects suck sap from the undersides of leaves. Their numbers can increase rapidly in dry weather above (70 degrees F) and plants can become infested. Solution: Malathion, Tree and Shrub Spray. Application: Mites can be difficult to control because of their high populations. Apply either malathion or Tree and Shrub Spray at the recommended rates. Be sure to spray the undersides of the leaves and the interior of the plant.
Symptom: Blossoms and twigs of fruit trees and members of the rose family turn black and die giving the plant the appearance that it has been burnt. Cause: The cause is Fireblight. This bacterial disease is most prevalent on pears and apples. The bacteria is spread by insects that travel from flower to flower, or plant to plant in the spring. Warm weather and high humidity or rain favour the spread of this disease. Solution: No chemical control is available. Application: Fireblight can only be controlled through proper cultural practices. Remove infected branches and twigs (10") below the infection, dipping your shears in alcohol or bleach solution after each cut. Avoid applying too much nitrogen fertilizer as this seems to increase incidence of disease.
Symptom: Dark brown corky spots appear on apples and pear trees, both on the fruit and on the leaves. In severe cases, fruit may be deformed and leaves may drop prematurely. Cause: The cause is Scab. This is probably the most common disease of apples. Fungal spores overwinter on dead leaves. In spring, rain discharges the spores into the air which infect young leaves and blossoms. Each new rainfall throughout the year causes new infections to occur. Solution: Fruit Tree Spray, Benomyl, Dormant Spray Kit. Application: Apply first spray of fungicide when the tips of the twigs turn green. Repeat every seven days until mid June and then once every ten to fourteen days until mid August. Raking up fallen leaves in autumn will help reduce incidence of disease.
Symptom: Leaves of many different types of plants appear cupped or curled. A sticky deposit called ‘honey dew’ is produced which may turn black with mold. Many small, soft body insects in various shades of green, brown or black are present on buds and the undersides of leaves. Cause: The cause is Aphids also known as plant lice. These insects suck sap from the plants, weakening them. Most plants can tolerate fairly high populations of these insects, but aphids do multiply rapidly and can overwhelm new shoots and leaves. Solution: Rose and Flower Dust, Rose Spray, Diazinon, Tree and Shrub Spray, Rotenone, almost any general purpose insecticide. Application: Aphids, although numerous are very easy to kill. Apply any general purpose insecticide as per the instructions, whenever aphids become numerous.
Slugs and Snails
Symptom: Irregular holes with smooth edges are chewed in leaves. Slim trails are noticeable on soil and plants. At night or on rainy days, slimy creatures are evident on plants or under leaves. Cause: The cause is Snails and Slugs. Members of the mollusk family, these creatures will eat many different types of plants. Females lay their white eggs in slime covered masses either in the soil, or under plant debris. Solution: Slug Bait Pellets and Beer. Application: Place pellets in small piles in areas you wish to protect. Cover with a board or pie plate to encourage slugs and snails to go there during the day. Repeat every two weeks or as needed. Some people also use a saucer of beer or a buried bottle of beer to control slugs. The creatures are attracted to the malt, fall in and drown in the liquid.
My personal choice for lawn care includes the services of a company. Their duties include lawn fertilizing, tree and shrub fertilizing, chinch bug control, grub control, core aeration, weed and crabgrass control, tree and shrub insect inspection and treatments.