Teff

A harvest-time nuisance shared with the other small grains - net or harvest promptly, since teff's shattering already loses seed to the ground.

Fruit disappearing from the outermost, most exposed parts of the plant first, and from the top of a tree where you cannot reach anyway. Single neat pecks and gouges in ripening fruit, with several fruits sampled rather than one eaten through - the classic sign that it was birds rather than an animal. Heads of grain or seed going visibly lighter and emptier as they ripen, with hulls and chaff scattered underneath. Freshly sown seed vanishing off the surface of a bed before it germinates. Bird traffic in and out of the plant picking up as the crop colors, and birds waiting on nearby wires and branches. Wasps arriving at the pecked and split fruit shortly afterward.

There is no treatment once a crop is being taken - only protection and timing, so the answer is to get netting on and to pick what is ready. Reflective tape, flash ribbon, spinners, and decoy predators do work, but only for a few days at a time: birds habituate fast, so move and rotate them and never rely on them as the main defense for a crop you care about. Cut and gather grain or seed heads a little early, at firm dough, and finish drying them under cover instead of leaving them standing for the flocks. Plant a little extra, or a decoy crop the birds prefer, and accept sharing anything that crops heavily. On a wild or foraged patch, fruit going to birds and small mammals is the point of the plant rather than a problem to solve.

Net, and net early. Bird netting draped over a frame or hoops so it stands off the fruit, with the edges closed at ground level, is the only thing that reliably works at harvest scale - and it has to go on before the crop starts to color, because once birds have found the food they are far harder to displace. Keep fruit trees small enough that netting them is actually feasible; that decision gets made years earlier, at planting. Bags of mesh, organza, or paper slipped over individual heads, clusters, or prize fruit protect a small crop without netting the whole plant. Then shorten the exposure: pick promptly and completely rather than leaving ripe fruit hanging as a lure, clear split and dropped fruit that draws birds and wasps alike, and where a crop can finish off the plant, harvest a little early and ripen or dry it under cover. Rake in or cover broadcast seed so it is not lying in plain view.

Birds find ripening fruit and seed before you do. Robins, waxwings, starlings, catbirds, jays, sparrows, finches, blackbirds, and doves all work a garden, and the pressure arrives in a narrow window - the last days before harvest, when sugar rises, color changes, and the crop softens or the grain hardens. A flock can strip a small planting in a day or two, and birds that only peck rather than take whole fruit still leave wounds that rot or draw wasps. Squirrels, chipmunks, and other wildlife usually turn up on the same crop at the same time. This is competition rather than disease: the birds are not harming the plant, and a big tree or a heavy-cropping bush often has enough for everyone - but on a small planting it can be the difference between a harvest and none.

Shattering plus the seed's tiny size make timely, careful harvest the crux of a teff grain crop - and the reason it self-sows readily.

Ripe seed falling from the heads when touched or shaken, and grain accumulating on the ground beneath an overstanding crop.

None once shattered - the dropped seed is lost (and will volunteer next year); prevention through timely, gentle harvest is the only answer.

Harvest promptly once the seed is hard, cut in the cool of the morning, and handle the cut plants gently onto a tarp to catch the seed.

The tendency of ripe seed to drop from the heads on its own - pronounced in teff because the grain is minute and only lightly held, so a crop left standing too long or handled roughly loses much of its yield to the ground.

Usually minor on teff - occasional and localized rather than a routine threat, and often managed by natural predators.

Ragged, chewed foliage and groups of striped caterpillars on the plants, sometimes appearing suddenly and moving across the stand.

Hand-pick on small plots, or use Bt (Bacillus thuringiensis) on young caterpillars; healthy teff often outgrows light feeding.

Encourage natural enemies (birds, parasitic wasps), keep the crop vigorous, and scout warm-weather stands so infestations are caught early.

Caterpillars of several moths that feed on grass foliage in groups, sometimes moving through a stand and grazing leaves and stems - an occasional pest of teff and other grasses, mostly in warm weather.