HORTICULTURE. 247 



varieties. Thinning: decreases the total yield. In experiments at the station, thin- 

 ning to 1 in. apart decreased the yield about 35 per cent and thinning to 2 in. apart 

 about 61 per cent. "Where the market does not discriminate in price between 

 medium sized and large plums, thinning will not pay unless the trees decidedly over- 

 bear. In this case it will pay for the benefit of the trees." In thinning, all plums 

 stung by the curculio should V)e removed. Early thinning is desirable, but late 

 thinning is better than none. The plums should be left not nearer than 1^ to 2 in. 

 apart. The value in thinning Japaneaes trees, the author thinks, is largely confined 

 to the good effects on the tree itself. 



Seedling trees of native plums at the station when not transplanted sometimes bear 

 freely the third year after planting. If transplanted the third spring, they bear the 

 following season. The plan followed by the station in testing seedlings is to thin out 

 the trees in the nursery row to 4 ft. apart the third spring after planting, which 

 allows of the fruiting of a part of the trees. Those thinned out are set in the orchard 

 5 ft. apart each Avay. It is claimed that the fruit borne by the seedling trees the first 

 2 bearing years will largely pay the cost of growing them. 



Descriptions of a number of native varieties, supplementary to those previously 

 given (E. S. R., 10, p. 45), are recorded. The varieties considered most promising 

 for market are Aitkin, Barnsback, Bomberger, Brittlewood, De Soto, Japan Cross, 

 Diana, Etta, Freeman, Hammer, Haag (when sprayed for rot). Hart De Soto, Nellie 

 Blanche, North Star, Ocheeda, Piper, Poole Pride, Quaker, Silas Wilson, Springer, 

 Surprise, and AVyant. "These varieties have been large in size, productive, and, 

 with few exceptions, excellent in quality." 



Under the caption of culinary uses for plums, directions are given for canning, 

 drying, preserving, and otherwise putting uji plums. 



In order to determine whether inclosing the blossoms in paper sacks, as is done in 

 experiments on the self-fertility or sterility of plums, has a harmful effect by shutting 

 out light, the ends of the branches of several varieties which gave evidence of bloj- 

 soming freely were inserted in large glass beakers, the mouth of the beakers being 

 closed with 2 thicknesses of cheese cloth. The branches in the beakers blossomed 

 normally and produced pollen in abundance, but in not a single instance did fruit 

 set. These results are taken as confirming the conclusions of Waugh that practically 

 all varieties of plums are sterile to their own pollen and must be cross fertilized. 

 The weight of the anthers, dimensions of the pollen grains, and number of stamens 

 of 21 varieties of Prunus americana, 3 each of P. domestica, P. triflora, and P. hortulana, 

 and 1 each of P. myrobalana and P. ungustifoliu, are shown in tabular form. The 

 author states that he is able to trace no relation between the productiveness of varie- 

 ties and the size of their anthers and pollen grains. The blooming season of a large 

 numbei" of varieties is given and the author states that a comparison of the records of 

 previous years shows that the order of blooming of different varieties is fairly con- 

 stant from year to year. 



To determine whether native varieties might not be propagated in the same man- 

 ner as the Marianna plum by cuttings, cuttings were taken from all the main vai-ieties 

 and seedlings of the Americana, Chickasaw, and Hortulana species. These were 

 jjlaced in the propagating Ijed in the spring and subjected to mild Ijottom heat for 

 several weeks. " With the single exception of the Marianna, all failed to root." 



An objection frequently made to Americana plums is the thickness and toughness 

 of the skins. "As a guide to breeding with the view of reducing the thickness of 

 the skin in the Americana plums, a brief study has been made of the skin of . . . 

 2 varieties of the Americana species, and 1 each of the Domestica, Trifiora, Hortu- 

 lana, and Chickasaw species." Illustrations are given of a c;ross-section of the skin 

 of the different varieties magnified about 15 times. The skin of Wildgoo.«e (Hortu- 

 lana) was found thinnest of all the varieties under observation. As this species is 

 regarded as a hybrid between the Chickasaw and Americana species, "there is every 



