296 BRITISH PLANTS 
officinalis (melilot), Ononis arvensis (rest-harrow), Filago 
germanica (upright cudweed), Matricaria inodora (scent- 
less may-weed), Bartsia Odontites (hemi-parasitic on 
grasses), Malva rotundifolia (dwarf mallow), Potentilla 
reptans (creeping cinquefoil), Polygonum aviculare (knot- 
grass), many species of Chenopodium (goosefoot). 
Commons.—In many parts of the country, within the 
region of cultivation, large stretches of waste land exist, 
on which the dominant plants are bracken, furze, and 
bramble. The soil is always very poor and dry, either 
sandy or stony. In many cases these commons are relics 
of cultivation. They are usually situated near towns, 
where land is valuable, and where every part of it is as 
far as possible utilized for raising crops, or used as pasture- 
land. Woods on dry soils have been destroyed, and the 
land experimented with in this way, but it has often 
turned out unprofitable, and the land has been allowed 
to go to waste. Rough grasses and herbs are the first to 
obtain a hold on the soil, and then larger plants, including 
the three which are now dominant. The association is a 
very mixed one, and of an open character. Birches, and 
often oaks, are more or less abundant, and it seems prob- 
able that in the course of time a Birch-Oakwood associa- 
tion will once more occupy the soil (see p. 271). 
The most abundant plants growing with the three 
dominant ones are dry-loving grasses—e.g., Festuca ovina, 
Aira flexuosa, Aira precox, Brachypodium pinnatum, 
Nardus stricta, and Agrostis vulgaris. Calluna vulgaris 
and Erica cinerea are often abundant, and many typical 
heath-plants—e.g., Thymus Serpyllum, Euphrasia offici- 
nalis, Lotus corniculatus, Hypericum pulchrum, Galium 
saxatile, Teucrium WScorodonia, Potentilla Tormentilla, 
P. reptans, Hieracium Pilosella, Rumex Acetosella. Veronica 
officinalis, Campanula rotundifolia, Stellaria graminea, 
Erodium cicutarium, Viola sylvatica, etc. Of woody 
plants other than those mentioned, the hawthorn, broom, 
and sloe are the most common. 
Many of the wider strips of roadside-waste are of this 
character. 
Cultivated Ground.—Where the land is_ periodically 
ploughed to receive new crops, weeds are very abundant. 
When the crop is in its seedling-stage, and earlier, the 
weeds have nothing to compete with, and can grow apace. 
