Q : Someone told me that it's a good idea to wash the leaves and needles of plants to control mites. Why should that be done? --J.T., Temple City
A: Dust that settles on leaves hampers beneficial predacious mites in their work against pest mites. Therefore, you should remove such dust occasionally with a stream of water. Control heavy mite infestations with Orthene or Kelthane.
Q: Before I plant bare-root fruit trees during their dormant season, should I prune off a substantial portion of the roots? I've been told that it's unnecessary, that the growers do it before shipping. --F.C., Claremont
A: Substantial root pruning by gardeners at planting time usually is not necessary. You should clip off broken root ends and those roots with wounds to minimize points of entry for pathogens. If quite a bit of the root system is removed, you can compensate by taking off some of the top as well, so that the tree is in balance in terms of its ability to take up enough water.