Get Down and Dirty

Apparently there is growing concern that crops are taking too long to emerge and will have to be reseeded. Those decisions cannot be made without getting down on hands and knees to determine what the seed is doing. This spring, in some areas, it is taking seven days before the seed coat even begins to crack so emergence is going to take even longer. When scouting, scrape back the soil and find the seeds or seedlings as their condition is an important indicator of germination/emergence. Hard seeds are probably an indication that conditions have been too dry and/or cold to facilitate germination. Unless most of the seeds are soft and seed decay is taking place, additional moisture and/or warmer temperatures may be all that is needed. If the seed coat is cracked, note the structure of the developing seedling. Seedling turgidity is a function of the emerging hypocotyl remaining rigid and having enough moisture to push through the soil surface. The healthy emerging hypocotyl will be firm and white. If moisture in the seeding zone runs out during emergence, the hypocotyl will dry out and discolour, often turning brown and wilt. This phenomenon is common in areas where soil surface moisture has dried out due to wind or lack of rainfall. The result is patchy emergence. It is often misdiagnosed as a seedling disease complex such as damping off. Cool, dry soil conditions are often the main culprit in poor emergence due to lack of seedling turgidity. If the warm temperatures forecast for the coming days arrive, canola emergence will happen quickly. Give the sun a chance to warm the soil for three to five days before making any decisions.