Camelina

An oomycete favored by cool, wet conditions that produces whitish-to-gray growth on the underside of leaves and on stems, pedicels and developing pods, sometimes with pale green to yellow blotching on upper leaf surfaces. Infections may be localized or systemic, and severely affected plants produce little seed, making this the most consistently damaging disease of the crop across humid and irrigated production areas.

Camelina is a confirmed host of the white mold pathogen, which infects stems under prolonged canopy wetness and high humidity and produces long-lived sclerotia that persist in soil. Stem infection weakens the plant and causes losses through lodging and premature ripening, and it also builds inoculum that carries over to other susceptible broadleaf crops in the rotation.

A mustard-family leaf and pod spotting disease that is favored by extended periods of high humidity and free moisture and can move onto pods late in the season, reducing seed fill and seed quality. It has been listed among the diseases of potential concern for this crop but has not yet caused major commercial losses, and pressure is lowest in dryland and semi-arid production.

Flea beetles are a major economic seedling pest of canola and mustard, and because camelina is a brassica it is exposed to the same overwintering beetle populations at emergence. In practice multiple extension programs report that camelina is markedly more tolerant than canola and that flea beetle feeding has not been observed to cause economic damage, so it is a watch item rather than a routine control cost.

Migratory leafhoppers transmit the aster yellows phytoplasma, which produces reddish discoloration and deformed, sterile flowers on infected plants. Cool, wet springs and high migratory leafhopper flights increase spread, but the disorder is largely cosmetic in this crop and has not been reported to reach economically damaging thresholds.

The crop is more drought and frost tolerant than canola, but excessive heat and moisture deficit during flowering and seed set sharply reduce harvestable yield. In hot, dry environments the same varieties that yield well over 1,500 lb/acre in cool sites can fall below 400 lb/acre, so heat at bloom is the single largest yield risk in most growing regions.

Pods hold seed more tightly than canola, but the crop ripens within days once color change begins and severe wind and rainstorms during that window cause high shattering losses. Excess nitrogen or a very heavy canopy also promotes lodging, which slows harvest and increases header loss of a seed too small to recover.

Fall-sown winter types are about as cold hardy as winter rye and can survive roughly -20F for several days with little snow, but most winter injury occurs in late winter from repeated freeze-thaw cycles and ice sheeting rather than from absolute cold. The crop also does not tolerate waterlogging, and rosettes sown into depressions that pond water in spring routinely die out.

There is no broad cash market for this seed; the crushing industry requires enough volume to fill a crushing run, so production is effectively grown only under private contract with a processor, and federal crop insurance coverage is likewise available only for contracted acres. Buyers and delivery points are geographically concentrated, and some contracts price the seed off soybean futures so the grower carries soybean-complex price risk on a crop with no futures market of its own.

Registered chemistry is extremely limited: weed control depends on a short list of burndown, preplant-incorporated and grass-selective products with essentially no broadleaf in-crop option, and fungicide and insecticide registrations are absent or minimal in most jurisdictions, so a field that becomes infested cannot be rescued. Compounding this, the crop is rarely named on other crops labels, so growers must infer plant-back intervals from canola or rapeseed guidance and are exposed to residual carryover injury from ALS-inhibiting and triazine chemistries.