| Provincial Situation: |
| Decade | Rank | Frequency (%) | Field Uniformity | Field Density (# m-2 ) | Relative Abundance | | All | Occurrence | All | Occurrence | | 1970s | 1 | 47.2 | - | - | 32.2 | 68.1 | 46.4 | | 1980s | 1 | 49.3 | 27.3 | 55.4 | 19.1 | 38.8 | 52.8 | | 1990s | 1 | 46.3 | 19.7 | 42.6 | 10.4 | 22.4 | 44.1 | | 2000 s | 1 | 37.3 | 15.2 | 40.8 | 8.8 | 23.6 | 48.8 |
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| Description: |
A clump-forming annual grass with seed-head that resemble fox’s tail, Stems are erect, branching at the base, 0.5 to 0.6 m in height. Leaves are flat without hairs; rough and pointed. Seeds clustered in a dense club that resembles a fox's tail. |
| Growth and Development (Life Cycle): |
Emergence: The main seeding emergence occurs in late spring as soil temperatures increase and coincide with crop emergence. Flushes occur throughout the summer especially after period of heavy rainfall. Seed Production: Panicle of green foxtail contains 350 –500 seeds. One plant is capable of producing 5000 – 12,000 seeds. Seed production is reduced if plants are growing under heavy crop canopy. Seed germination: Germination occurs readily at temperature 15°C – 35 ° C. On the Prairies, green foxtail germinates from late May through late June, however, flushes may germinate up to September. Dormancy: Dormancy may lasts for 4 – 10 weeks, or longer if it is dry. Longevity in the soil: Shallowly buried green foxtail seeds remain viable in the soil for up to three years Dispersal: By wind water and via contaminated seed and feed. |
| Where it Grows (Habitat & Ecology): |
Green foxtail is very common and widespread throughout all agricultural regions of Alberta. It grows well in all soil textures and occurs in cultivated lands, waste places, roadsides, gardens and occasionally lawns. |
| How it Spreads (Mode of Spread): |
Cultural and chemical control methods to reduce wild oats and broadleaf populations have contributed to the increasing infestation of green foxtail. Shallow tillage in the early spring along with delayed seeding commonly used in the past has provided ideal conditions for green foxtail germination. Use of broadcast fertilizer, especially high rate of nitrogen encourage its rapid growth and competitiveness. Green foxtail is a prolific seed producer; continuous cropping increases the potential of rapid build-up of green foxtail seed. |
| Economic Importance (Beneficial Aspects): |
Detrimental: Individual of green foxtail is not strongly competitive. Under certain conditions, however, large population can substantially reduced grain yields. Green foxtail is most competitive under high light and warm temperature conditions. Green foxtail that emerge earlier in the season is generally more competitive than later emerging plants. |
| Origin: |
Eurasia |
| Flowering: |
Main flush of weeds begins to flower in mid-July, green foxtail that emerges later flower through the summer. |
| How to Control: |
Management Strategy Prevention of seed production is the key to controlling green foxtail. Cultural Options: Tillage: Fall or early spring tillage is little vale to control this weed. Moreover, tillage contributes to soil erosion. Seed early – Any crop which establishes itself early, will compete with the green foxtail mainly because green foxtail seedlings emerges in mid June and will not be able to compete with the vigorous crop stand Seeding rate – Seed heavier than normal to encourage a competitive crop stand. Rotations – Summerfallow reduces green foxtail, however, on the Prairies the practice of summerfallow is declining. Three to four years of perennial forage crops will also decrease green foxtail population. Cereals and oilseeds are the most difficult crops in which to reduce green foxtail populations. If these crops are seeded earlier and heavier than normal, they should prevent further infestation of green foxtail. Mowing – Mowing of perennial forages is effective if done before green foxtail produces seed. However, seed are usually viable in mid June before hay is ready to cut. Chemical Control Options |
