Plant community response to integrated management of meadow hawkweed (Hieracium caespitosum) in the Pacific Northwest

John M. Wallace, Timothy S. Prather, Linda M. Wilson

Research output: Contribution to journalArticlepeer-review

7 Scopus citations


Meadow hawkweed is an invasive, perennial forb of upland forest openings, mountain meadows, permanent pastures, and abandoned farmlands in the Pacific Northwest. The objective of this study was to measure the plant community response, following meadow hawkweed control using selective herbicides and a single application of NPK fertilizer, across three levels of meadow hawkweed infestation in cleared forestlands that had been converted to pasture in northern Idaho. Clopyralid was applied to meadow hawkweed rosettes at a rate of 0.59l kg ae ha-1 (0.528 lb ac-1), and fertilizer (23-5-5, 1% Fe, 14% S) was broadcast following herbicide applications at two rates, 44 and 88 kg N ha-1. Foliar cover of meadow hawkweed, Idaho fescue, and other perennial grasses was measured in microplots at three levels of initial meadow hawkweed cover; <25%, 40 to 60%, and >75%. Clopyralid treatments resulted in excellent meadow hawkweed control 3 mo after treatment (MAT). Clopyralid alone appeared to shift the competitive balance in favor of perennial grasses, which increased 7, 44, and 65% above pretreatment levels in LOW, MED, and HIGH hawkweed cover plots, respectively, across fertilizer treatments. Meadow hawkweed cover remained <5% in clopyralid plots at 52 MAT. Fertilizer effects were confined to interactions between Idaho fescue and other perennial grasses.

Original languageEnglish (US)
Pages (from-to)268-275
Number of pages8
JournalInvasive Plant Science and Management
Issue number3
StatePublished - Jul 2010

All Science Journal Classification (ASJC) codes

  • Plant Science


Dive into the research topics of 'Plant community response to integrated management of meadow hawkweed (Hieracium caespitosum) in the Pacific Northwest'. Together they form a unique fingerprint.

Cite this