Native grasses are widely used in the Intermountain West for restoration and conservation of semi-arid rangelands negatively impacted by exotic weedy annuals and recurrent wildfire. Their utilization, however, is typically limited by low seed yields and poor establishment. To address this, Destination Germplasm Snake River wheatgrass (Elymus wawawaiensis J. Carlson & Barkworth [Poaceae]) was released by USDA ARS on 31 May 2023. Destination Germplasm was developed directly from 'Discovery', released in 2007, being selected for emergence from deep seeding in the greenhouse, which is a generally recognized technique to improve seedling vigor and spike numbers in the field. Establishment-year (2021) biomass of Destination Germplasm exceeded 'Secar' by 118.1% and Discovery by 51.3% at North Park Farm (Hyde Park, Utah). Across 2 seed-production years (2022–2023), Destination Germplasm biomass and seed yield exceeded Secar by 41.0% and 43.7%, respectively, and Discovery by 24.4% and 78.3%, respectively. Likewise, for seed mass, Destination Germplasm exceeded Secar by 25.5% and Discovery by 16.1%. When fall-seeded at Nephi, Utah, in 2022 on an equal seed-number basis, 2023 stand establishment was 65.8%, 34.0%, and 11.5% for Destination Germplasm, Discovery, and Secar, respectively. This calculates to a 93.5% and 66.6% increase in establishment for Destination Germplasm relative to Discovery when sown on an equal seed-number and an equal mass basis, respectively. A strong positive correlation (r2 = 0.958) was found between seed mass at North Park and establishment percentage at Nephi. Destination Germplasm will facilitate improved establishment and seed-production success relative to its predecessors, Secar and Discovery.
Ništix or grizzleybear pricklypear (Opuntia ×columbiana Griffiths (pro sp.) [fragilis ×polyacantha] [Cactaceae]) was grown under solar panels and in full sun. We compared the survival and production of transplanted pads and the morphology of new pads. Survival rate of transplanted pads under the solar panels was much higher (90 ± 2.6%) than in the full sun (17 ± 5.5%), which were subject to decay due to a heavy snow event. The solar panels protected the pads against heavy snow burial, likely contributing to their higher survival rate. Productivity of the transplanted pads under the solar panels was much higher than those in full sun. This finding was measured by the number of new pads produced relative to the number of remaining pads, which was approximately 300% higher under the solar panels. The new pads under the solar panels were etiolated and twice as long as those in full sun. Overall, this preliminary study suggests that O. ×columbiana can be propagated successfully under solar panels, which could have implications for this tribally significant species and for land management.
Sand dropseed (Sporobolus cryptandrus (Torr.) A. Gray [Poaceae]) is a native, warm-season perennial bunchgrass that has value in conservation seedings in the Intermountain West. US Department of Agriculture, Natural Resources Conservation Service, Aberdeen Plant Materials Center conducted 3 experiments to determine whether seed treatments could improve percent germination and coefficient of germination (CG, germination speed) of various accessions of sand dropseed. The effects of temperature, scarification, cold-moist stratification, and germination in Petri dishes or aerated water baths (bubblers) were investigated in a growth chamber. Initial Petri dish experiments with one accession at optimal germination temperatures indicated that scarification did not increase final percent germination (FPG) at 14 d after initiation (DAI) but did increase CG from 7.9 to 10.4. Scarification did not increase FPG or CG at 28 DAI at suboptimal temperatures. A larger study with 3 accessions and 8 treatment combinations of scarification, stratification, bubblers, and Petri dishes at optimal temperatures found the highest FPG and CG for each accession occurred with scarified seed germinated in Petri dishes. In some cases, stratification alone improved germination, but in other cases, it resulted in lower germination due to fungal growth. For all 3 accessions, germination in Petri dishes was superior to that in bubblers. These results suggest that scarification, and possibly stratification (both of which can be used for field-scale plantings), may improve the success of sand dropseed establishment in conservation seedings.
Milkweed species provide breeding sites and food essential for the survival of monarch butterflies (Danaus plexippus L. [Lepidoptera: Nymphalidae]) that overwinter on the California Coast and migrate inland to other western states. Showy milkweed (Asclepias speciosa Torr. [Asclepiadaceae]) is widely distributed throughout Northern California; however, populations have declined for a variety of reasons including discontinuation of indigenous stewardship methods, a transition to rangelands dominated by weedy annual grasses, and an increase in intensive agriculture. Although seed and greenhouse materials are commercially available, establishment rates are discouraging. We evaluated field establishment of plants grown from seed, rhizomes, and 3 planting times for transplants (fall, early spring, and late spring) in California's San Joaquin Valley. Evaluations were conducted during 2018 and 2019 for germination and survival, plant height, disease damage, and insect damage. Establishment and survival were rated as moderate to excellent for all planting methods. Showy milkweed rhizomes had the highest rated establishment and survival rates in both the 2018 and 2019 growing seasons and were tallest in height. All fall and spring transplants showed good establishment during both years of the trial. Despite having the lowest establishment scores based on percentage of propagules established, seeding in the fall had the highest estimated plant densities after 2 y; however, seeded plots required significant hand weeding. Insect and disease damage was significant among all planting methods.
