NEW NEW PLUM J a m S e s s i o n™ B l u e s J a m™ Robert L. Andersen, Jay Freer and John Watson Robert L. Andersen, Jay Freer and John Watson Department of Horticultural Sciences, NYSAES, Cornell University, Geneva, NY Department of Horticultural Sciences, NYSAES, Cornell University, Geneva, NY

It proved to be exceptional in the quality attributes products’ shelf life. Due to its high performance in of its processed products when compared to pilot processing trials conducted by food scientists, Damson and other commonly grown we anticipate acceptance of Blues Jam™ products by domestica . While trees of Jam Session™ are consumers. Arbor Hill of Naples, NY, has been hardy and crop heavily, they tend to biennial selling a preserve made from Blues Jam for several bearing if over-cropped. Nevertheless, it warrants years. release for its usefulness as a processed ingredient Blues Jam™ resulted from hybridizing ‘Furst’ of plum products. with an unknown male parent. Seeds of open Jam Session™ is partially self-fertile. Hence, it pollinated trees of Furst were saved in 1958 by John may benefit from interplanting with a pollenizer P. Watson (deceased), a senior research associate in that is known to bloom simultaneously the former Department of Pomology and Viticulture with it and known to successfully pollenize its (now part of the Department of Hort. Sci.). In 1970, flowers. Two successful pollenizers for it are Watson selected and propagated the seedling tree Damson and NY 9™. It ripens in mid-September in that he designated as NY 58.904.1 because its fruit Jam Session™ Geneva, about a week after Stanley. Its skin color is was similar to Damson and it cropped very heavily. dark blue and unprocessed flesh is yellow-. In subsequent trials at Geneva and on New York am Session™ is a unique processing plum. Due to Neither the skin nor the flesh are astringent. farms this selection was designated as NY 9041. J its high performance in pilot processing trials Processed jams and jellies of like Jam Trees of Blues Jam™ proved to be hardy and crop conducted by food scientists, we anticipate ready Session utilize whole fruit with pits extracted after heavily with little tendency to be biennial, and are acceptance by consumers of New York- grown Jam initial cooking. The color of cooked Jam Session™ self-fertile. Moderate mite susceptibility is its only Session™ products. Most of New York’s on-farm fruit is a beautiful deep, purple-red and this color is known fault. retailing includes jams and jellies, which often are slow to oxidize to brown. Fruit are round-oblong Blues Jam™ ripens in mid- September in produced in small kettle batches by the fruit farm and approximately 3/4” wide and 7/8” long and Geneva, about a week after Stanley. The fruit weigh families. Additionally, many of these farms also sell weigh approximately 15g. approximately 20g, which is slightly larger than Jam both their fresh fruit and fruit preserves in cities and The tree has medium vigor and is readily Session™. They have blue skin and green-amber villages where farmers’ markets and green markets trained to systems that use machine harvesting via flesh and are approximately 1” long and 3/4” wide. afford access to locally grown products, often shake and catch methods. It has strong fruit reten- Processed jams, jellies and sauces of plum products through on-the-spot sample tasting. Jam Session’s tion that resists natural drop, but tree structure and containing Blue Jam™ blended with milder flavored, preserves can assist New York fruit growers as they bearing habit favor fruit removal via centrific force. Blues Jam™ less well colored, cultivars gave excellent taste test seek new, value-added items to retail or wholesale. Hence, fruit can wait on the tree for scheduled results and had long shelf life stability. Fruit are Jam Session™ resulted from hybridizing ‘Late harvest. Trees require annual pruning once mature lues Jam™ is a unique processing plum that completely freestone and oblong in shape. Muscatel’ with an unknown male parent. Seeds of to reduce crop loads and encourage annual bearing. B resembles Damson in astringency that requires The tree has medium vigor and is readily open pollinated trees of Late Muscatel were saved Black knot and brown rot tolerances of Jam Session recipe management. As with Damson, the machine harvestable via shake and catch methods. in 1958 by John P. Watson (deceased), a senior are similar to that of Damson (above average). The astringency can be managed in several ways. Black knot and brown rot tolerances of Blues Jam™ research associate in the former Department of pit of Jam Session™ fruit is completely freestone Freezing and thawing the fruit before processing are similar to that of Damson (above average). Pomology and Viticulture (now part of the and oblong with dimensions of 1/2” x 5/8”. moderates astringency and improves color. Trees of Blues Jam™ are available from Deptartment of Hort. Sci.). He selected and propa- Trees of Jam Session™ are available from Astringency can also be moderated by blending commercial nurseries. Such nurseries must acquire gated the seedling tree that he designated as NY commercial nurseries. These nurseries must acquire with a less astringent fruit such as Jam Session their legal permit to grow this trademarked cultivar 58.911.1 in 1970 because it had wonderful plum their legal permit to grow this trade marked culti- and many other plums. It has favorable processed from International Management, Inc., of taste. In subsequent trials at Geneva and on New var from International Plant Management, Inc., of color and good flavor that helps the final Lawrence, MI. York farms, this selection was designated as NY 111. Lawrence, MI.

24 NEW YORK STATE HORTICULTURAL SOCIETY NEW YORK FRUIT QUARTERLY • VOLUME 14 NUMBER 1 • 2006 25