Each fall our lawn is littered with short twigs of Norway spruce. At first we thought the trouble was some insect and sprayed with malathion. Now we suspect squirrels. If so, how damaging are squirrels, and how can we stop them?

Short twigs littering the lawn are just a nuisance. Squirrels do cut off the terminal shoots, or the leader, of conifers to feed on the buds. Some deformity in the tree may result, but this shouldn't be noticeable unless the feeding is excessive.

There are two methods to control squirrels: trap the culprits in wire cages baited with nuts or apples, then take them a few miles away and free them; or feed them, so they won't be tempted to eat the buds.

In fall 1995 we planted wisterias but they have never bloomed; otherwise, they grow nicely. Is this normal?

Wisterias can take many years to flower - if they ever do. There is a 100-year-old wisteria vine at the Arnold Arboretum in Boston that has never bloomed. These vines need good drainage, full sun and plenty of moisture.

Root-pruning and an application of super-phosphate will force some wisterias to bloom. I forced a 4-year-old vine to bloom by applying super-phosphate at Thanksgiving. Sprinkle around the base of the plant and work into the soil. Winter rains will get the substance to the roots of the vine, and you might have blooms next spring.

When my tulips bloomed last spring, the petals were covered with brownish flecks about 1/4-inch long. Can you identify the problem?

Botrytis blight (also called "Fire blight") becomes prevalent when there is heavy rain. Leaves and petals of infected tulips are flecked with small brown spots, which may coalesce into large areas. Infected flowers and leaves should be destroyed. If the infestation is severe, remove infected plants, bulb and all, as early as possible.

To protect tulips, dust or spray once a week before they flower in the spring with a fungicide such as captan, zineb or ferbam. The blight can rot bulbs if unchecked.

Contact Tim Morehouse by Web site: www.getmoregarden.com; mail: c/o the Enquirer (enclose a self-addressed, stamped envelope.)