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Data on the net production of oven-dry organic matter from 28 temperate angiosperm herbaceous species and 4 temperate arboreal species were analyzed to determine the relationship between below-ground and above-ground yearly increment. Mean yearly net herbaceous production (t/ha) was 3.9 for below-ground parts, 5.9 for above-ground parts, and 9.8 total. Mean yearly net arboreal production (t/ha) was 1.9 for below-ground parts, 8.9 for above-ground parts, and 10.8 total.The mean below-ground/above-ground ratio and mean below-ground production was significantly higher for herbaceous species. Mean above-ground production was significantly higher for arboreal species. There was no significant difference between total herbaceous and total arboreal production. Productivity comparisons based only upon above-ground parts are likely to be biased in favor of arboreal species.In herbaceous species, root production decreased with age and increased from fruit crops to root and tuber crops and the below-ground/above-ground ratio increased from moist to mesic to xeric species. Arboreal species were uniform in below-ground/above-ground ratios.

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Concentration of chlorophyll per unit area of land surface was measured for six forests and 13 native and managed herbaceous stands in central Minnesota. Chlorophyll samples were extracted in acetone and in ethyl ether, and spectro-photometric analysis made of chlorophyll a and b content. Wet and ovendry weights of the aboveground crop were determined.A highly significant correlation was found between the dry weight of the aboveground crop of the annual herbaceous stands and the chlorophyll content of these stands. All stable natural herbaceous stands had an approximately similar ratio of chlorophyll to the dry weight of aboveground parts.Chlorophyll content in grams per square meter of land surface along an upland gradient from field crop through native communities of increasing age or successional development or both was Zea mays (2.7), Soja max (0.9), younger to older successional stages of old field (0.3 to 0.6), native prairie (0.7), xeric (more open) savanna (0.6), mesic (less open) savanna (1.0), conifer–hardwood forest (3.1). Chlorophyll content for a pond hydrosere from the Nymphaea odorata margin through Carex lasiocarpa mat to Chamaedaphne calyculata shrub and Larix laricina forest increased from 0.3 to 1.4 g/m2. Values for a younger and older Populus tremuloides lowland grove were 1.7 and 5.9 and for a Typha marsh were 4.6 g/m2.These data showed a tendency for later successional stages to exceed earlier stages, for some lowland stands to exceed upland stands, for forest to exceed herbaceous communities on a given moisture level, and for field crops to exceed prairie and old field. The upland old field to forest sequence and the lowland Nymphaea to Larix sequence had similar chlorophyll contents for a given stage of successional development. There was a highly significant positive correlation between chlorophyll content and height of the arboreal stands, and a significant positive correlation between chlorophyll content and herbaceous stand height.A significant difference in chlorophyll content was found between all stands with three or more sample plots, except those with closely correspondent mean values. The maximum difference between stands was twentyfold, which does not support previous studies which have suggested a similarity of chlorophyll content in diverse communities.Chlorophyll concentrations and wet and dry weights per various plant parts are presented for the seven tree samples, and the presence of chlorophyll in other than leaf parts emphasized.