6.4 Arable farming and gathering
No comparative research has been done in the field of the vegetable component of the diet, mainly for practical reasons such as lack of time and insufficient data. Carbonised remains of chaff and grains of naked barely and emmer were found at all the sites. This, combined with carbonised seeds of marsh plants (which are assumed to have been field weeds) and especially the occurrence of silica gloss on some flint knives showing that they were used as sickles, is at Schipluiden taken to be a strong argument in favour of local crop cultivation. It is plausible that crops were cultivated at Wateringen, too, though this site yielded less evidence to support such an assumption. Sickle gloss was also observed on a few tools at Ypenburg. The absence of ard marks may not be taken as a counterargument: the settlements predate the earliest ard marks so far found in the Netherlands (Louwe Kooijmans 2006b), it is far from clear precisely where the fields lay, so also whether any parts of fields may have been included in the excavated area, and the soil conditions were not favourable for the preservation of any ard marks.
Besides practising crop cultivation, the sites’ occupants also gathered produce in nature: onions, tubers, root vegetables, nuts, berries, fruits. Most prominent among the archaeological remains are the remains of sloes, which evidently grew in the dune shrubs all over the place.