Filbert Production

Abstract

The filbert, Conjlus avellanaL., is a primitive angiosperm plant that, when compared to other fruit trees, possesses many unusual traits:

It is monoecious, self-sterile, and wind pollinated. Its female flowers lack petals, nectaries, sepals and ovary. At the time of pollination the rudimentary flower consists of 2 styles joined at their base by a few meristematic cells that ultimately become the ovary.

In areas of commercial production the filbert blooms in mid-winter. In Oregon, bloom usually occurs from mid-January to mid-February.

As much as half a year can elapse between pollination and fertilization. The pollen tube grows to the base of the style and becomes quiescent until the ovary and ovules are developed in June and July.

Because the flowers initiate in August of one year, and the nuts develop in August of the next year, the apex of the nut is more than one year older than its base.

The filbert plant habit is bushy, but in the United States filberts are trained to grow as single trunk trees.

In mild climates the filbert appears to be growing throughout the entire year. This is due to the separately timed activities of the male catkins, the female flower clusters and the vegetative buds. Defoliation in November is followed by early blossoms in December.