With night-time temperatures occasionally dropping below freezing in the Mesilla Valley, area pecan producers are looking toward harvest time. They are also looking forward to a good per-pound price for their product again this year, although yields are likely to be smaller due to the drought.

Some of the oldest pecan trees in the valley can be found on the campus of New Mexico State University, according to Richard Heerema, NMSU Extension pecan specialist. Research on pecan varieties has been conducted at the university for nearly a century.

Earlier this month, Heerema was walking through the old pecan orchard at the university's Fabian Garcia Science Center west of the Las Cruces campus, noting the differences among the trees and sampling the occasional nut. The orchard covers approximately four acres on the west side of the research center. He and many of his fellow faculty members believe this orchard's first pecan trees were planted by the legendary Fabian Garcia, the first director of the university's Agricultural Experiment Station, who is best known today for his pioneering work in chile pepper development.

Heerema says that based on trunk girth, some of the orchard's approximately 120 pecan trees certainly appear old enough to have been part of that original planting.

In the 1925 Agricultural Experiment Station Bulletin 145, "Preliminary Pecan Experiments," Garcia and co-author A.B. Fite refer back to the March 1916 planting of pecan trees "on the Horticultural Farm where an old peach orchard had been removed." Two or three trees were planted of 17 different varieties obtained from Texas and Indiana, with the idea of testing their adaptability to New Mexico growing conditions.

This "College Experimental orchard," as they termed it, was populated with the following varieties: "Stuart, Money-maker, Schley, Colorado, Pabst, Frotscher, San Saba, Van Deman, Venus, Texas Prolific (Sovereign), Success, Indiana, Busseron, Niblack, Green River, Warrick, and Kentucky."

A few of the oldest-looking trees in the orchard today still have rusting metal tags identifying them as belonging to some of those varieties: ROW 7 TREE 6, KENTUCKY; ROW 1 TREE 4, STUART; ROW 4 TREE 2, VAN DEMAN.

It is unlikely that all of the varieties mentioned by Garcia and Fite are currently represented in this orchard. There are also whole rows of smaller trees that clearly could not have been part of the original experimental orchard set.

"There's a good deal of variation from tree to tree in this block," says Heerema, standing under one of the older trees. "There's a lot of variation in bark texture, for instance. This one has a very shaggy-textured bark, whereas others have a much smoother bark. You'll also see a good deal of variation in the shape of the pecan nuts, the ripening date, the flavor, the growth pattern or the structure of the tree, a lot of variation in this orchard block."

Nut analysis

Last year, Heerema sent off a collection of fresh nuts from the orchard's largest and oldest-looking trees to L.J. Grauke of the USDA Agricultural Research Service's Pecan Breeding and Genetics program.

In a recent email to Heerema, Grauke reported some "very tentative" identifications based on the physical characteristics of the nuts. Of the nearly 20 suspected varieties, five cultivars (San Saba, Stuart, Success, Van Deman and Western) did match the 1916 Garcia-Fite list, but Grauke said it appeared that most of the cultivars "date from the mid-20th century."

The range of ages and varieties is the result of generations of NMSU pecan researchers having had projects here, among them Roy Harper, Darrell Sullivan and Roy Nakayama.

Geno Picchioni, NMSU horticulture professor, reports a telephone conversation he had with Darrell Sullivan in 1999, 17 years after the latter retired. Sullivan reported to him that Harper had grafted and top-worked many of the existing trees in that orchard.

According to John Mexal, also a professor of horticulture, Sullivan's work included fertilizer work on pecans, while Nakayama was more exclusively focused on breeding.

And Esteban Herrera, retired NMSU Extension horticulturalist, said it was Nakayama's work on pecans at the science center in the early 1970s that led to the registration of the pecan cultivar "Salopek."

Pecan varieties released by NMSU in 1967 and 1983 are named after Harper and Sullivan, respectively, attesting to the importance of their work.

The orchard's value for future research is questionable.

"This orchard is very different from the way standard commercial orchards are set up today, and as such, the main value of this orchard really is its historical value, the fact that it was probably planted by Dr. Garcia himself," Heerema says. "But there may actually be some valuable genetic resources within this orchard.

"We don't know what the cultivars are of each of these trees, but we do know that there is a good deal of diversity, in terms of which trees are here. Some of these are probably very common cultivars, but some of them may be very rare cultivars, some of them may be seedling trees, some of them may be cultivars which are extinct elsewhere. So there may actually be some very interesting genetic resources, possibly for use in breeding programs in the future."

In addition to appreciating the heritage value of the orchard, Heerema also brings classes out to give them some first-hand knowledge of varietal differences and of some of the disease challenges pecan trees face in New Mexico. 

NMSU's pecan research program has spread out to several other locations. In the Mesilla Valley, Heerema is doing research in an established 11-acre orchard and an additional 20 acres of recently planted pecans at the Leyendecker Plant Science Research Center south of Las Cruces. NMSU currently has more than 60 total acres of pecans for research purposes at Leyendecker and at its agricultural science centers in Los Lunas and Artesia. The inventory includes more than 3,000 young seedlings donated over the past two years by Linwood Nursery of La Grange, Calif.

Meanwhile, back at the old Fabian Garcia Science Center orchard, the orderly rows of trees provide a nice park-like feature for the adjoining residential neighborhood. The nuts will be harvested and sold as soon as they are ready, according to farm manager Mark Pacheco. Whatever the orchard's future research value may be, many of its trees are still producing a crop of tasty nuts.