Ricerche sulla, Flora Infestante delle Colture in Italia

Summary

The author has studied the flora infesting the cultures of the hills of Val d'Elsa. The soil showed a marked alkaline reaction. On the whole 208 species were collected and classified according to Fiori. In the biological spectrum therophytés prevail.

The rotation in the land taken in consideration is quinquennial and wheat is sown amidst lucern; the investigations were carried on on the various cultures of the rotation, using Raunkiaer's method.

The author has drawn up a list of the various species found in every cultivation followed by a description of the biological cycle of the most important ones. In addition he has tried to explain the preference of several species for certain fields an their absence in others sometimes placed very near.

The author has then pointed out

a) the most dangerous weeds of the cultures examined;

b) the months during which the infesting flora reaches its maximum;

c) the species which develop their biological cycle during Summer and those which have a shorter biological cycle.

A study has been also carried on on the influence of cuts on the second-year lucern fields and. the harvesting of wheat sowed in the first-year lucern fields for what concerns the F% of the weeds.

Lastly the author has made a brief phytogeographical analysis of the principal weeds examined.