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Barley heading date has advanced in Fairbanks (64.83° N, 147.77° W), Alaska, USA. However, it is unclear if this advance coincidently causes weather pattern changes around heading and leads to yield loss. Using the Variety Trial and weather data in Fairbanks and Delta Junction (64.05° N, 145.60° W) from 1991 to 2018, two barley cultivars were selected to analyze the yield and weather trends, the yield variation explained by weather, and the effect of extreme weather on yield. The results showed that the heading date of ‘Otal’ significantly advanced and yield significantly declined in Fairbanks while there were no heading and yield changes of ‘Otal’ in Delta Junction and of ‘Thual’ in both Fairbanks and Delta Junction. The weather pattern changed around heading due to advanced heading of ‘Otal’ in Fairbanks. The climate factors at 7–10 days around heading explained over 50% of ‘Otal’ yield variation in Fairbanks. The results suggest that ‘Otal’ can still be good to plant in Delta Junction but not in Fairbanks. To cope with the climate change in Alaska, the farmers should increase the diversity of barley cultivars, select non-photoperiod sensitive cultivars and cultivars with longer duration from planting to heading, and sow late to avoid the impact on heading and yield.

Vegetative growth of lingonberries was observed on plants growing in four unsterilized, native-Alaskan substrates: coarsely-ground Lemeta peat, Fairbanks silt loam soil, a mixture of peat and silt loam soil and washed Chena very fine sandy loam soil. Following three growing seasons, plants in the peat treatment showed the greatest increase in vegetative growth as revealed by the number of new stems produced, stem length and dry weight per plant. Leaf size did not differ among substrate treatments. The leaves on plants grown in the peat substrate remained green throughout the entire experiment. The leaves of plants in all other treatments showed varying degrees of chlorosis followed by reddening and necrosis. Differences in concentration of N, P, K, Mn, Fe, Zn and Al in whole-plant tissue samples were recorded. The results indicate lingonberries should be grown in a peat substrate for maximum growth and dry matter accumulation.

Regeneration surveys on nine logged areas in the vicinity of Fairbanks, Alaska indicated low levels of white spruce (Piceaglauca (Moench.) Voss.) regeneration. In view of the limited field data, Monte Carlo simulation methods were used to estimate the probabilities of obtaining various levels of white spruce stocking by the 1st and 10th years after logging. The simple model developed, combined the irregular seed production of white spruce with a declining seedbed availability to estimate quadrat stocking (4-m2 plots). Results of simulation experiments indicated that the probability of achieving greater than 40% stocking with white spruce by the 10th postharvest year was 0.63. This result was sensitive to initial postharvest seedbed conditions and the frequency of good to excellent seed years and nonspruce revegetation rates. Both the field data and simulation results indicate the prospects of obtaining adequate white spruce restocking after timber harvest by unassisted natural regeneration were poor. However, simulation results also indicate that seedbed management may increase the probabilities of regeneration success significantly.

Fall seed-dispersing species, birch (Betulapapyrifera Marsh.), alder (Alnuscrispa (Ait.) Pursh), and black spruce Piceamariana (Mill.) B.S.P.), and summer-seeding species, aspen (Populustremuloides Michx.), balsam poplar (P. balsamifera L.), feltleaf willow (Salixalaxensis (Anderss.) Cov.), Scouler willow (Salixscouleriana Barratt), and Bebb willow (Salixbebbiana Sarg.), were artificially sown on seedbeds created by experimental burning in the upland black spruce/feather moss forest types in interior Alaska. At least 40% of the seeds dispersed in the fall had germinated before dispersal of summer seeds began. Germination occurred on moderately and severely burned seedbeds but not on scorched and lightly burned surfaces. Seedling survival occurred almost exclusively on severely burned surfaces. After 3 years, 82% of the plots containing some severely burned surfaces and sown with seeds from species seeded in the fall were stocked whereas 32% of the plots sown with species seeded in the spring and with the same seedbed condition were stocked.