Every year HTIRC staff and students harvest hundreds of pounds of seed to support forestry researchers and nursery stakeholders, especially the Indiana Division of Forestry’s Vallonia State Nursery. Starting this year, the HTIRC also began supplying seed from select seed trees to Tree Pro for private distribution.
Spring came early in 2024, with bud break occurring two weeks sooner than normal. The rapid warmup accelerated flowering in the walnuts, thankfully with no late frosts to destroy female flowers. Accordingly, walnuts throughout Indiana bore heavily, with the notable exception of orchards at Martell and the Lugar Forestry Farm, which yielded a bumper crop last year. Despite these shortages, the HTIRC was still able to provide select black walnut seed to the Vallonia State Nursery by harvesting at grafted walnut orchards located elsewhere. Twenty-two bushels (~22,000 seeds) of cleaned bed-run walnut and 8,000 select black walnut seeds were also supplied to the state nursery. About 6,000 black walnut seeds from selected clones were also harvested for Tree Pro’s HTIRC Select lines.
The warm spring also led to a productive butternut crop in some of HTIRC’s orchards and screening blocks. Eighty-six new seedling genotypes (genetic identity) were harvested this year for nut phenotype (physical appearance) research, with seed from butternut canker disease-resistant seedlings and grafts allocated for Tree Pro’s HTIRC Select lines. Assisted by Forest Service staff, forty bushels of pure butternut were harvested this year from the Hoosier National Forest’s pure butternut conservation orchard in Huntingburg, Indiana. Pure butternut from the OFS orchard is distributed between Hensler Nursery, Tree Pro, and the new Buckeye State Nursery in Zanesville, Ohio.
The black cherry crop was mediocre this year, with clones from Indiana and Michigan primarily producing. No seed was harvested for progeny testing, but about 10,000 seeds were harvested for the IN Division of Forestry select seedling line.
Red oak bore sporadically this year, with spotty crops on wild trees throughout the state. Seed from improved seedling seed orchards at Martell suffered greatly from seed predation and poor seed fill, with only 20% of seed harvested being viable. Use of catch-nets and diligent monitoring allowed the HTIRC to supply the Vallonia State Nursery with 3,000 select red oak acorns, but harvest totals still fell well short of what was needed.
Wild white oak crops were heavy. Seed from wild trees throughout the state was harvested for the HTIRC’s newest white oak grant in collaboration with the University of Kentucky. Surplus seed was sent to Vallonia. The HTIRC’s white oak orchards bore less than last year, with very heavy seed predation again taking its toll at the HTIRC’s grafted precocious white oak orchard. Regardless, enough seed was harvested for progeny testing of 25 families and delivery of 7,000 select white oak acorns to the Vallonia State Nursery.
American chestnut crops continue to be modest, with the heavily blighted Duke grafted orchard bearing only sporadically depending on individual tree health. About 5,000 pure American chestnut seeds were harvested for distribution through Tree Pro and the Buckeye State Nursery. Several controlled crosses were made this year, primarily creation of new F1 (first crossing) American x Chinese hybrids. Using pollen supplied from The American Chestnut Foundation, novel F2 (second crossing) American x Chinese crosses were made to further the development of a blight-resistant American chestnut hybrid.
By Caleb Kell, Operational Tree Breeder