Further, we have on our Sleeping Giant Plantation, Hamden, Conn., several hybrids, now 16 years old, of the Seguin and the Chinese chestnuts, the former species being also a native of China, but dwarf and everblooming and remarkably prolific. These hybrids are excellent as nut producers, since they inherit the large-sized nut of the mollissima parent, combined with the increased productivity of the Seguin parent. Furthermore they are extremely blight-resistant.[33] These hybrids have therefore been intercrossed among themselves this year, chiefly for the benefit of the Italian people. One hundred and eight nuts from reciprocal crosses of these hybrids were shipped to Italy. Also, in response to a request, we sent nuts of our best Chinese and Japanese trees and of the mollissima-seguini hybrids to M. C. Schad of the Station d'Amelioration du Chataignier, Clermont-Ferrand, France.
[33] These hybrids will shortly be put on the market, under the sponsorship of the Conn. Agr. Expt. Sta. and the Division of Forest Pathology, U.S.D.A. As regards the everblooming habit of the Seguin parent, that character seems to be lost or at least partly suppressed. A second flowering of one of the hybrids usually occurs in August.
~Other crosses.~ Two Chinese-American trees in our plantation at the White Memorial Foundation near Litchfield, Conn., bore a considerable number of female flowers this year for the first time. They have been crossed with the fine Japanese tree of Mr. A. N. Sheriff at Cheshire, Conn., figured in my report for 1948-49. (P. 92, fig. 3, of 40th Rept. of N.N.G.A.) From them, 75 nuts were harvested of the combination CAxJ. Four crosses were made on the trees at Redding Ridge, Conn., in the cooperative plantation of Mr. Archer M. Huntington, resulting in 73 nuts. Also, the resistant Americans on Painter Hill, Roxbury, Conn., were again crossed with CJA's and Chinese from our Sleeping Giant Plantation and from these were obtained 247 nuts. Finally, we have this year succeeded in making a cross between Castanea henryi, the Henry Timber Chinkapin from southern and central China, which is said to attain a height of 90 feet, and C. mollissima, the Chinese chestnut. Since henryi blooms very early, much before our mollissima, the Division of Forest Pathology mailed us pollen of C. mollissima, which reached us just in time to be applied to henryi. Seven good nuts of this cross were gathered.
Altogether, as the overall result of our cross pollination work, we harvested 1259 nuts, more than twice as many as obtained in any other year since we began this work in 1930.
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TABLE 1
Heights of Some of Largest Trees, as of Oct. 1, 1950.
All at Sleeping Giant Plantation, Hamden, Conn.
Species or Height
Hybrid Location Age in yrs. in ft. Remarks
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J × A Row 4 Tree 10 19 30 Repeatedly inarched
J × A " 4 " 4 14 33 Grafted on Jap.
stock, Apr. 1937
J × A " 4 " 12 19 29 Repeatedly inarched
J " 7 " 5 20 23
C " 1 " 4 24 30-3/4
CJA " 60 " 39 13 29
CJA " 61 " 48 13 24
CJA " 8 " 8 4 14 Grafted on Chinese
stock, spring, 1947.
Fruited this yr.
1st time.
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J=Castanea crenata
A=Castanea dentata
C=Castanea mollissima
~Nuts, Scions and Pollen Received.~ During the fall of 1949 we received nuts from New Hampshire, Mass., Conn., N. Y., N. J., W. Va., N. C., Ohio, and Ill. Scions were received in March and April from Mr. R. M. Viggars of the Bartlett Tree Expert Co. station at Wilmington, Del. (C. dentata); and from Messieurs Schad and G. A. Solignat, Centre de Recherches Agronomiques, Clermont-Ferrand, France, (C. crenata and sativa.) During June and July, pollen of C. dentata came from Mr. E. J. Grassmann, Elizabeth, N. J., Mr. Paul Maxey, Montcoal, W. Va., Mr. Malcolm G. Edwards, Asheville, N. C.; C. mollissima and dentata from the Division of Pathology, U.S.D.A.; C. sativa, vars. pistolese and selvatico from Dr. Aldo Pavari, Stazione Sperimentale di Selvicolture, Florence, Italy; and C. pumila and dentata from Mr. Alfred Szego, Flushing, N. Y. This list is presented as evidence of the widespread interest in our work. It is a pleasure to acknowledge this cooperation and to thank the many donors. We are especially glad to report that several "catches" have been made with the C. sativa scions from France and those of the tall mollissimas at Mt. Cuba, Del., from Mr. Viggars.
May I again caution those who send us nuts not to allow them to become dried out. The embryos, when dried, are killed. The nuts should be wrapped in moist cotton, peat moss, or something similar, and mailed to me not later than a few days after harvesting, at 255 South Main Street, Wallingford, Conn.
~Insects, bad and good.~ The cankerworms were rather destructive in May at our Sleeping Giant Plantation (not at the others) but fortunately later than usual. The mite, Paratetranychus bicolor, attacked the leaves of some of the trees on the Sleeping Giant Plantation rather late in the season, so that on September 8 we sprayed with the Station's power sprayer, using Aramite effectively. Shade and humidity seem to favor the spread of this pest. Japanese beetles appeared but have never been very destructive with us. As happened last year, we sprayed twice for the weevils, August 14 and September 8, with excellent results.