A Persian Walnut Project For New York Nut Growers
Persian (Hardy English) Walnut is the nut from the "Garden of Eden", which suffered much from its ejection to the New World. No more disease control by walnut tree and environment. No more warm, moderated, predictable climate. No more cute, short, non-reincarnating winter. So now this nut, a nut that has been a staple of "humans" while they expanded their brain cases, is suffering in New York. It does not survive the harsh highlands, and acid soils, but many varieties deliver sweet, melting kernels at 600 feet above mean sea level at locations moderated by open water, and at many locations below 300 feet msl.
The main disease of Persian walnut is bacterial blight of walnut. Wet conditions generate black cankers on green vegetation of leaves, shoots, nuts, and bark. The brown spots that destroy the growth of graft wood, cause fissures in the bark of second year wood on trees. Growing tips often turn black and shrivel to look like winter injury though it is still summer. More exasperating is the drop of dew that clings to a nut and starts the black canker where it hangs on the bottom of a nut. Several applications of copper spray will keep the blight off graft wood, but repetition seems never enough to preserve the nut crop, likely due to that drip on the nut. It is not time to throw up our hands and give up. Several blight resistant selection have been brought to the hill country of Texas from the USSR by Dr. Loy Shreve of Texas A & M. Sylvania and S3 are the Shreve selections with which we have been working, while Lake is a well-known variety that delivers bright nuts with a minimum of spraying. These are enough to start a project to breed workable New York Persians. If we get more from Texas, or the new gatherings of Tom Molnar of Rutgers, it will increase our rate of success. The University of California, Davis, California, maintains germ plasm for Persians if we can gain any that are blight resistant and hardy.
The Wisconsin Horticultural Society sold $1 per nut Carpathian walnuts in the late 1930s. These produced hardy English walnuts in the US, but only in locations with late spring frosts and moderated climates. Their lack of blight resistance was soon discovered. Many of these trees are still growing in NY, and cropping well, due to the large size these trees achieved, getting above the near ground conditions of frost and blight. Lake may be one of these Carpathians though it is not a typical Carpathian. Lake has blight resistance, and very hardy pollen buds. Our search for blight resistance turns up these trees, but they will have to be inspected for blight.
As a nut growing association we need to be known for nut growing endeavors. Persian walnut bred for New York may be our best project. Everyone knows what English walnuts are. They know that they are more rewarding, and easier to open than pistachios. They probably don’t know that New York walnuts are far tastier than California’s Diamond brand. They know that walnuts are good for health as an anti-oxidant, and a health substitute for fish and its oil.
What we can advertise to discover; what we need in NY:
à We need superior NY hardy English walnut with signs of blight resistance.
à We need grafting sites where black walnuts are growing that can be top worked 4’ & up.
à We need people to watch grafting sites and their crops.
à We need people to plant resistant seed and seedlings.
à We need to set up one day to service any planting on DEC land.