million garden owners and bird lovers want to do the feathered residents of our Parks, gardens, and suburbs, by laying out of bird food. Most of the time it is finished bought grain and seed mixes, millet, sunflower seeds and other nutritious seeds contain. In the case of titmouse dumplings, these grains are mixed with additional fat and tallow. Studies show that at least some bird species definitely benefit from such feeding by producing the following spring, for example, more young.

weed seeds in almost all mixtures

But it is not always only what is on the package containing these feed mixtures. Frequent studies have found that, in addition to sunflower seeds, millet and other seeds of field are weeds or even potentially invasive non-native plants included in these mixtures. The share of these unwanted seeds, and which seeds are represented especially often now Erik Oseland from the University of Missouri and his colleagues. For their study, ordered and bought a 98 different varieties of in the USA, commercially available bird feed and studied its composition.

It showed: In almost all Grains foreign seeds were included as contamination – overall, the researchers found the seeds from 29 different arable weeds classified plants. Among these species were common species such as Bindweed (Fallopia convolvulus), blood-red finger millet (Digitaria sanguinalis), or amaranth-also invasive species such as broom-Radmelde (Bassia scopari), or ragweed (Ambrosia artemisiifolia). This from North America to Europe, introduced species produces highly allergenic Pollen and is spreading in Germany rapidly. Oseland and his Team found the seeds of this kind particularly frequently, in feed mixes containing lots of sunflower seeds.

Propagation for invasive species

additional germination tests showed that 19 per cent of the amaranth and foxtail seeds from the bird food germ were capable of. Overall, Oseland and his Team found seeds in 98 percent of the bird feed mixtures of weeds. In the home garden or in the Park, such consist of arable weeds, although rarely a Problem, but if the birds carry these seeds, for example, on organically managed fields. “Although it is difficult, the role of the commercial bird feed accurately assess,” says Oseland. “But it is very likely that it is a hitherto overlooked Propagation of unwanted and problematic weeds in new areas.

source: Cambridge University Press; article: Invasive Plant Science and Management, doi: 10.1017/inp.2020.2

*The contribution of “Invasive seeds in the bird food” is published by Contact with the executives here.