Rangeland Ecology & Management

Get reliable science

EFFECTS OF NEIGHBORING PLANTS AND DEFOLIATION ON GRASS SEEDLINGS AFTER FIRE IN SAGEBRUSH COMMUNITIES
Author
Gicklhorn, Jeffrey M.
Newingham, Beth A.
Publisher
Society for Range Management
Publication Year
2018
Body

Native perennial bunchgrass species are often seeded after wildfire in the Great Basin to stabilize soils and resist invasive species establishment. Domestic livestock grazing is typically postponed for two growing seasons to allow for seedling establishment. Seeding failures may occur due to unsuitable abiotic conditions or inappropriate post-fire grazing management leading to seedling mortality. We explored how post-fire grazing management and neighboring plant communities affect the efficacy of post-fire seeding treatments in Artemisia tridentata ssp. wyomingensis communities. We implemented plant removal treatments at the beginning of the first growing season to vary the relative density of adult and seedling perennial bunchgrasses. Growing and dormant season defoliation treatments were used to simulate livestock grazing and examine the appropriate time to reintroduce livestock after fire. We repeatedly sampled perennial seedling tiller stem length, leaf and flower production, and timing of senescence during the first three growing seasons to quantify plant-level responses. We sampled end-of-season perennial bunchgrass plant density and foliar cover for the first three years to quantify treatment effects on community structure. Adult and seedling removal decreased plant density and foliar cover in the first year after fire. Foliar cover in adult removal treatments recovered as compared to neighbor removal control treatments by the second year, while seedling removal cover remained reduced in through the duration of the study. Fall and spring defoliation within seedling removal hastened senescence following defoliation, while spring defoliation decreased inflorescence production during year two only. Seedling mortality did not differ by treatment, and none of our treatments reached the recommended benchmark for livestock reintroduction of 20% bunchgrass foliar cover after three growing seasons post-fire.

Language
English
Resource Type
Text
Document Type
Conference Proceedings
Conference Name
SRM Reno, NV