Two New Mahoberberis Hybrids

TWO new Mahoberberi.s-hybridshave been growing in tlie Arnold Arboretum since 194-8 when they were first obtained from Sweden.These are decidedly different, one from the other, but apparently both have possibilities as ornamental broad-leaved evergreens in those northern areas where ^lahonia aquljb/iinn proves hardy.They have been growing out-of-doors during most of this period, without special winter protection.They have neither fiowered nor fruited, but appear sufficiently interesting for their foliage alone, to be a welcome addition to the all-too-small group of broad-leaved evergreens suitable for northern planting.It must be said that one of the parents, Mahouia aquijolium , though twig hardy in many northern gardens, does have foliage injury in late winter, especially if grown in the full winter sun, and such may also be the case with these two new hybrids.It is recommended that both of these be planted in situations where they have some winter shade.After further trials in various parts of the country, we will know more about their hardiness limits than we do at present.Mr. Holger Jensen of Ramlosa, .Sweden, noticed these first in 19L8 as new hybrid seedlings and reported them in a Swedish y)ublication, but did not describe them, and in 194-8 sent over two small plants of each to the .Arnold .Arboretum for trial.In 1950, Mr. (Jert Kriissmann, Curator of the Dortnumd-Brunninghausen Botanical (iardens in (ierrnany, prevailed upon .Mr.Jensen to send him photographs and a few twigs from the hybrids, and it was from these that Mr. Krussmann |)repared the first foliage sketches and dcscrii)ti()n of these plants, published in his Deutsche Bauiuschule {WA.2: 12, pp..SOO-.SO 1 , .SIO) for December 1950.J'he United .States De{)artment of .Agriculture passed rigid regulations in 11*18 ( Uederal (^uarantirie No. 88) concerning t he shipment of certain plants including Maliouia, Mulioberberis, and Berberis, which were known to carry the serious black stem rust of wlieat, and these restrictions liave ht t ii ,'1111111} n in -it t iilr since that time.Lengthy exjierimentation on the part [ <)