How long do weed seeds live?</

Jan 17, 2017

Researchers have found these seeds can survive for years

By Patrick Lynch

Farms.com

There are numerous research papers looking at this question. It is hard to do research on this topic. How do you have “natural” conditions? How do you know how many weed seeds were there at the start?

Researchers bury weed seeds or plant them to get an idea. The results showed that annual grass seeds germinated earlier than broadleaf weed seeds. Typically, over 50 per cent of annual grasses germinated in the first year. Bad news is that there were still 4 per cent of grass seeds viable after 17 years.

Annual broadleaf weeds had a similar germination pattern with fewer germinating in the first years and more still viable in the longer term (11 per cent of broadleaf weeds were still viable after 17 years.)

Research from Minnesota showed that there were over 130 million weed seeds/ac. In this study surprisingly wild oats only lived for three to six years but lived longer if buried deeper.

Lamb's quarters
Photo" Manitoba Agriculture

Another study reported that lamb’s quarters can live for 40 years. All of this suggests that we have to go back to “weed free” fields. Especially since we have so many resistant species.

Dow’s new Enlist™ and Monsanto’s Roundup Ready 2 Xtend™ will help control some already herbicide-resistant species but this resistance will also break down eventually. You have to be conscious of building the weed seed bank. Use of cover crops is the most economical way to reduce some weeds from setting seeds.

Video: Will the 2025 USDA December Crop Report Be a Market Mover/Surprise?

Historically, the USDA December crop report is a non-event or another dud report as the USDA reserves any final supply changes to the final report in January of the following year in this case 2026. But after the longest U.S. government shutdown in history at 43 days and no October crop report will they provide more data/surprise and make an exception?
Our China U.S. soybean purchase tracker is now at 26.6% or a total of 3.2 mmt but for traders it’s taking too long to unfold.
The final Stats Canada production report was bearish canola and wheat projection a record crop in both (it adds to the global glut of supplies) and bullish local corn and soybean prices in Ontario/Quebec thanks to a drought. It will not help the fund flow short-term, the USDA may need to offset it?
A U.S. Fed interest rate cut of another 25-basis point next Wednesday (probability 87.1%) could help fund flow and sentiment in stock and ag commodities into year end.
More inflows into Bitcoin this past week saw prices rebound back above 90,000 with support at 82,000 and resistance at 96,000.
A V-shaped bottom in cattle suggest the lows are in after Mexico reported another new world screwworm case. Lower weights, seasonal demand and higher U.S. beef select/choice values with a continued closure of the Mexican border to cattle will result in a resumption of higher cattle futures into yearend.
Australia is expected to produce its 3rd largest wheat crop ever at 36 mmt adding to the global glut of supplies.
Reports of ASF in hogs in Spain the largest pork exporter in Europe could see the U.S. win more pork export business long-term.
If the rains verify into next week of 3-5 inches for Brazil it would go a long way to fixing the dry regions from the last 2-months, but the European weather model has been wrong for the past 2-months!
Natural gas futures are surging to the 3rd price count as frigid hold temps set in.
CDN $ is also surging to end the week on a very resilient economy and better employment numbers suggesting no interest rate cuts next week.
Finally, the CFTC report showed funds were net buyers of soybeans but sellers of corn, canola and wheat. In real time the funds have gone back to selling as they take some profits.