Q: Is it too late to do anything about pear psylla? I have read to use dormant sprays, but of course the leaves are out now.

Every year, these things burrow into the pears and ruin them. I forgot to spray earlier. What kind of dormant spray should I use next year?

– Elizabeth Kuehner, Sacramento

According to UC Master Gardener Bill Pierce, pear psyllas are treated with a delayed dormant oil spray usually in January to kill over-wintering adults and to smother eggs.

You may use either a dormant oil or, if the tree has leaves, one of the lighter-weight summer oils. During the growing season, psylla damage results in sticky fruit and foliage that becomes black with sooty mold.

Vegetative growth becomes stunted or the tree is defoliated and there are beads of clear, sticky honeydew enclosing tiny yellowish insects on the leaves. Infestations during the growing season are treated with summer oil sprays.

You mention "things" burrowing into the fruit. Those are coddling moth larva.

Codling moth larvae are white to light pink "worms" with a dark brown head. They are one of the few worms that are likely to be found inside pear or apple fruit.

Information on the codling moth is available at www.ipm.ucdavis.edu. This information also is available by sending a self-addressed, stamped business-size envelope to: Pest Note 7412, UC Cooperative Extension, 4145 Branch Center Road, Sacramento, CA 95847.

Information on winter care of fruit trees will be available at the upcoming Fair Oaks Horticulture Center workshop on Jan. 21. More information on the workshop will be available at cesacramento.ucdavis.edu in December.

Q: I have a corn plant growing in our family room. It has grown so that it is now touching the ceiling. Is it OK to cut it at the top?

– Dorothy Reardon, Carmichael

Indoor corn plant (Dracaena fragrans 'Massanglana') should be pruned in the spring or summer, says UC Master Gardener Bill Pierce.

Simply cut off the stem at the height you desire; new foliage will grow at the cut.

The cut-off stem can be cut into pieces (about 6 to 12 inches is a good size) and rooted for new plants. The old top will also root.

Use a mixture of half peat moss and half sand or perlite as the rooting medium. Keep the mixture damp but not soggy and place your cuttings in a shady place until growth is apparent. Then, gradually bring them into stronger light and repot them using a good grade of potting soil.

Your original plant can be left in the house after pruning or moved outside to a covered patio or lathhouse, where the new top will grow.

GARDEN QUESTIONS?

Questions are answered by master gardeners at the UC Cooperative Extension services in Sacramento and Placer counties.

Send questions to Garden Detective, P.O. Box 15779, Sacramento, CA 95852. Send email to h&g@sacbee.com. Please put "Garden Detective" in the subject field and include your postal address. To contact your UC Extension directly, call:

• Sacramento: (916) 875-6913; 9 a.m.-noon and 1-4 p.m. weekdays

• Amador: (209) 223-6838; 10 a.m.-noon Monday through Thursday; email ceamador.ucdavis.edu

• Butte: (530) 538-7201; 8 a.m.-noon and 1-5 p.m. weekdays

• El Dorado: (530) 621-5512; 9 a.m.-noon weekdays

• Placer: (530) 889-7388; 9 a.m.-noon on Tuesdays, Wednesday and Thursdays or leave a message and calls will be returned

• Nevada: (530) 273-0919; 9 a.m.-noon Tuesdays through Thursday or leave a message

• Shasta, Tehama, Trinity: (530) 225-4605

• Solano: (707) 784-1322; leave a message and calls will be returned

• Sutter, Yuba: (530) 822-7515; 9 a.m.-noon Mondays and Tuesdays and 1-4 p.m. Thursdays

• Yolo: (530) 666-8737; 9-11 a.m. Tuesdays and Fridays, or leave a message and calls will be returned

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