Problem Weeds - A Cattlemen's Guide

Livestock producers are increasingly aware of various problem weeds. The presence or absence of these plants indicates the health of the pasture and hay land where found. Their presence usually leads to their increase and subsequent economic loss. Producers should realize that livestock will normally not consume these plants unless forced to.

Problem weeds include:

• Absinth
• Baby's-Breath
• Curlycup Gumweed
• Downy Brome
• Scentless Chamomile
• Tansy
• Toadflax

Since these plants can be deleterious to animals or at the very least unpalatable (providing limited or no weight gains), it is important that producers be familiar with their identification, successful control or eradication methods, and ways to prevent further infestations.

Many persistent pasture weeds are herbaceous perennials introduced from Europe. When Western Canada was settled at the turn of the century, these plants were seeded by pioneers for both ornamental and medicinal purposes. With the abandonment of many homesteads over the years, many plants have spread beyond their original site into range, pasture and hay land.

Please be aware that this information is for educational purposes only. It is not recommended for medicinal and/or herbal purposes, as the information was gathered from a number of references and therefore not accurate.

Producers should follow a weed or invasive plant strategy that includes:

• Prevention;
• Early detection and eradication; and
• Containment and integrated control.

Prevent the introduction of new weeds. Monitor to detect new introductions early and eradicate using hand pulling or herbicides. If invasive weed problems become too large to successfully eradicate, then they should be contained and not allowed to spread using a boundary buffer zone, while integrated management methods are applied within the containment zone to reduce the negative impacts of the invasive weeds.

Below are some useful tips for activities to fit into your integrated plan:

1. Be able to identify the plant.
2. Review present management techniques.
3. Walk and check fields - windshield surveys are not accurate indicators, as the extent of the infestation often goes undetected.
4. Avoid equipment contamination - clean tillage, grain and forest harvest equipment between fields; also clean road maintenance equipment.
5. Tarp grain trucks or otherwise contain weeds to the vehicles that grain or forage is moved in. Plastic wrapping of bales to be moved long distances is a viable alternative.
6. Purchase clean seed and feeds. Make sure to thoroughly read the field inspection sheet prior to forage seed purchase. If clean feed is unavailable or prohibitively expensive to access, isolate the feed and livestock being fed to a confined area in order to isolate weed seeds that will be excreted in their manure. This is to facilitate the monitoring and eradication of any new weed introductions, before they spread and become a production concern.
7. Do spot spraying.
8. Remove initial infestations while still small, either by hand or with herbicides.
9. Maintain a uniformly competitive grass cover to prevent and/or reduce an infestation in pastures, roadsides and non-crop areas.
10. Prevent seed set/formation by mowing/swathing before flowering.
11. Harvest and till weed-infested areas separately.
12. For shallow rooted plants, rogue infested areas and put plants in a garbage bag to dispose of through burning or deep burial.
13. If the weeds are cut while in flower, bale up the weeds. The bales can later be destroyed by burning.
14. Consult the provincial Guide to Crop Protection for herbicide control. Read and follow label directions carefully. Use licensed applicators where required.
15. Keep a sense of humour.