plant food in the surface soil lint not in the subsoil

50 24.   Soil in which earthworms have been living and making burrows 55 25.   Fresh soil turns milk bad, but baked soil does not 57 26.   Soil contains tiny living things that grow on gelatine 58 27.   Our breath makes lime water turn milky 59 28.   Something in the soil uses up air and makes lime water turn milky 61 29.   Soils are able to stick to water: clay or loam soils do this better than sands 65 30.   Water can pass from wet to dry places in the soil, it can even travel upwards 66 31.   Plants growing in soils supplied from below with water. All the water the plants get has to travel upwards 67 32.   Mustard growing in soils supplied with varying quantities of water 69 33.   Wheat growing in moist and in dry soils 71 34 a and b.   Plants found on a dry soil had narrow leaves, those on a moist soil had wider leaves.
Phot. S. T. Parkinson 72, 73 35.   Plants give out water through their leaves 74 36.   Stephen Hales's experiment in 1727 75 37.   Hill slope near Harpenden showing woodland at top and arable land lower down.
Phot. Lionel Armstrong 77 38.   View further along the valley; woodland and arable above, rough grassland near the river.
Phot. Lionel Armstrong 79 39.   Rough grass pasture near the river. Higher up is arable land.
Phot. Lionel Armstrong 81 40.   After harvest the farmer breaks up his land with a plough and then leaves it alone until seed time.
Phot. Lionel Armstrong 83 41.   Rolling in mangold seed on the farm.
Phot. H. B. Hutchinson 85 42.   Soil sampler 88 43.   Cultivation and mulching reduce the loss of water from soils 90 44 a and b.   Maize cannot compete successfully with weeds 94, 95 45.   A plot of wheat left untouched since 1882 at Rothamsted has now become a dense thicket.
Phot. Lionel Armstrong 97 46.   A badly drained wheat field