One of the more familiar nuts is the walnut. This group includes English, Persian, or Carpathian Walnut (Juglans regia), Black walnut (J.nigra), Butternut (J.cinera), Heartnut (J.ailantifolia cordiformis), and a few other minor walnuts. They are characterized by large tree size, deep taproots, sensitivity to frost, high timber value, and excellent nut quality. Walnuts are monoecious, having separate male and female flowers on each tree. Most walnuts are cross-compatible (a Black walnut will pollinate a Persian walnut, for example), but often suffer from the problem of being protandrus (producing male pollen first and later female bloom) or protogynous (producing receptive female bloom before pollen is available).

The adaptive tactic here is to plant walnuts in small groves so that pollen is always available to blooming flowers. They are wind-pollinated and thus need to be in close proximit.

Good qualities to look for in walnuts are large annual production, late vegetating, early maturity, high percentage of kernel, and easy cracking of the nut, bearing on lateral branches in addition to terminal branches, and multiple nuts per cluster.

Ecologically, walnuts function as upper story "climax" species in their area of origin. Being long-lived, deep-rooted trees, they are drought resistant and contribute substantial deep nutriet cycling to smaller and shorter-lived understory species. The Black walnut roots, leaves, and nut husks contain a chemical called juglone that restricts growth of other plants, being a defensive mechanism to reduce competition in the wild. Other walnuts seem to have less, if any, problem from this influence, unless Black walnut is used as the rootstock on grafted walnuts.

Walnuts require a deep, well-drained soil and favor neutral to alkaline pH. While somewhat slow growing at first, they will begin bearing in 3-6 years. Walnuts are an excellent multiple-use nut tree, yielding high quality nuts, valuable wood (Carpathian walnut is know as Circassian walnut in the trade), good shade (especially heartnuts), and minimum pest problems or pruning requirements. Of special interest are grafted walnut trees of known parentage.

Our nursery is working on many new varieties that will be coming in the next few years, and have Heartnut rootstock for areas with hard pan problems. We use both Black and Heartnut rootstock for grafting our Heartnut varieties.

We look forward to serving our customers' needs and producing well-grafted trees for you.

Yours truly, Sidney L. Grinnell