At seed-growing the aim is to produce a commodity with high germination capacity, good soundness and purity, and also slight admixture of seeds from other species. The capacity of germination and the vigour of the seeds may become impaired in consequence of mechanical damage, infection of diseases, growth of mould, attacks of vermin, high drying temperature, secret germination, sprouting in the ears etc. The germ belongs to the outer and most unprotected parts of the seed, and consequently this is much exposed. Even quite sound seeds can instantaneously have low capability of germination. It can be due to the fact that the seeds are in rest of germination, i.e.

1. Reaction on burial depth and nitrogen availability and placement in competition with a crop In this trial it was investigated how couch grass (Elymus repens) changes its ability to compete in stands of wheat and barley with different burial depth and different amounts and placement of nitrogen. More knowledge in this area can be valuable in the attempt to decrease the use of herbicides and still keep the weeds under control. The trial was carried out in the summer of 2004 as an outdoor pot experiment. The pots contained 15 litres of soil with a surface of 0,06 m2.

In the middle of the 19th century came an opposite reaction against the hospitals? treatment of their patients and a more human way was requested. A link between crowded housing, bad hygien and other bad conditions had been noticed and nature was considered to be healthy. Hospitals and sanatiories moved closer to nature due to influences from England, USA and Germany, and cities began building public parks. Employment was seen as calming and healthy for the patients.