arundinacea – from Latin arun, meaning reed

Native range: Europe and Asia

Leaves:

• flat
• 5–15 cm wide
• roughened
• sheaths open
• margins overlapping
• ligules:
  • 4–10 mm long
  • usually tattered and turned backward
  • slightly hairy
  • no auricles

Flowers/Fruit:

• panicle
• compact (initially)
• 8–15 cm. long, but the branches somewhat spreading
• 3-flowered spikelets, strongly compressed, crowded on side branches of the inflorescence
• glumes about the same size, slightly unequal, 4–5 mm long, minutely hairy, 3-nerved
• fertile lemma to 4 mm long, shiny, flax-like, 5-nerved
• sterile lemmas to 2 mm long, brownish, hairy, 2-nerved
• bloom time: June to July

Other characteristics:

• robust perennial grass growing 2–6 ft. (2 m.) tall
• long, scaly, pinkish rhizomes
• hollow stems

Relevant info:

• hyperaccumulator species capable of removing contaminants and excess nutrients through bioremediation
• called ‘canary grass’ perhaps because P. canariensis is source of canary seed, or because genus was first described in Canary Island
• Note: There is some debate about whether or not there was/is a native strain of this species, but it is listed as non- native according to botanists and evolutionary biologists of the UW Herbarium. Currently, it is a major threat in wetland areas and restoration sites, where it forms monocultures and prevents establishment of native species, so in this course we focus on the need for control.

Ecology & Adaptations:

• native to Eurasia
• found in wet places, usually where disturbed, especially along roads, streambanks, and open fields
• scattered and often locally abundant, more common in the southern portion of PNW
• at low to middle elevations around areas of human habitation or agricultural activity
• dense rhizomatous mat prevents other species from establishing
• vegetative reproduction:
  • rhizomes can extend over 10 ft/yr
  • extensive mat-producing system that prevents other species from becoming established
  • detached stems or rhizomes grow into new plants when in contact with bare soil
• control:
  • combination of methods required
  • digging rhizomes (any remaining will continue to reproduce)
  • mowing/cutting, disking or tilling
  • burning can be pre-treatment for disking/tilling if conducted in the fall, but must occur earlier in the year to diminish growth (but generally not possible to get burn permits for earlier periods)
  • excavation (in prep for restoration sites), but all plant material must be disposed of off site or buried beneath 2 ft of soil
  • cover with shade cloth for two growing seasons
  • sheet mulching with cardboard plus 4 inches of wood chops plus dense (2–3 ft apart) planting of willow stakes (to create shade) has been successful in Puget Sound (at CUH!)
  • aquatic formulations of herbicides (glyphosates, imazapyr) with appropriate application methods (including repeat treatments) and permits