Between 1966 and 1969, Forest Service Plant Geneticist Hoy Grigsby installed the last of his tree improvement studies on the Crossett Experimental Forest (CEF). This research, a series of plus-tree progeny tests of full- and half-sib loblolly pine (Pinus taeda
), was installed to compare the survival, form, vigor, fusiform rust resistance, and height growth of these families (and CEF “woods-run” sources). Due to a variety of reasons, this study was discontinued in the 1970s. Recently, we have started to investigate the remaining trees in this now 48- to 51-year-old superior pine progeny test. This initial report summarizes what is known about the 1969 outplanting and considers what may be possible for future research. Although past thinnings mean this research can no longer document survivorship or fusiform response, valuable information on growth and yield can still be extracted. For example, comparisons of “winners” and “losers” based on 3-year height outcomes are not consistent with those noted on a more limited sample after 48 years of growth.
plus-tree progeny test
Bragg, Don C. 2018. Superior pines revisited: a plus-tree progeny test on the Crossett Experimental Forest at a half-century. In: Kirschman, Julia E., comp. Proceedings of the 19th biennial southern silvicultural research conference; 2017 March 14-16; Blacksburg, VA. e-Gen. Tech. Rep. SRS-234. Asheville, NC: U.S. Department of Agriculture, Forest Service, Southern Research Station: 158-166.