Juglans regia, the cultivated Persian walnut, has only about twelve species of fungi recorded from it in this country. There are, undoubtedly, more to be found. Of these fungi the walnut bacteriosis, caused by a bacterial germ is more important than all the rest of the parasites put together we can easily say. The California walnut bacteriosis has turned up at various points in the East. The twig blight form of this disease is also prevalent in various states. The walnut blight or bacteriosis is therefore to be figured with in planting the Persian walnut in the East.
Professor Smith: Is it worse or better here than in California?
Professor Waite: There have not been enough walnuts grown here in groves to allow the disease to accumulate—to have a fair test for that, Professor Smith. I don't believe we know; but it is, undoubtedly, a parasite of our native black walnuts. It occurs in Texas and Louisiana, and I think we have it in or near Buffalo, N. Y., and in New Jersey, so if I were planting extensively I should expect that disease to be serious. That would be my forecast of the matter. The humidity and the cloudy weather in the East ought to be more favorable to the disease than the climate of California.
Mr. Jones: For that reason I should think the disease would work fast in the Gulf Coast.
Professor Waite: Yes, those specimens of yours seem to show a very serious condition.
We must not pass over the chestnut without noting that there are thirty species of fungi attacking it, and that does not include the new one, the bad one, the chestnut bark disease.
The filbert blight belongs with the diseases of the European grape and sweet cherry. The filbert is an example of a European plant introduced into the eastern United States attacked by a native parasite which almost drives it out of cultivation. In fact, there are so few filberts in cultivation even now that if we were trying to plan a spraying experiment on them we would not know where to find a plantation suitable for carrying on the experiment. If any of you know of any such plantations I would like you to let me know about them.
The Chairman: We will have some in two or three years.
Professor Waite: Here is a sample of the filbert fungus taken from our pathological collection. It shows the mature fruiting bodies of the fungus and it also shows that the twigs are killed. This fungus is known as Cryptosporella anomala. It was described as Diatrype anomala by Peck of Albany, N. Y., but was afterwards found to belong to another genus. There have been two or three articles published on it, the best one probably by Humphrey in Massachusetts. I have an abstract of that which can be copied in the proceedings, if you wish.