GEOLOGY, RELIEF AND DRAINAGE

The brooks therefrom would never, one would suppose, have been powerful enough to strip so large an area. Did the Cole once join the Rea across this patch? Its present course suggests diversion at some early time. The extensive quarrying in south Saltley was not responsible for the stripping, for it occurred on a small part only of the uncapped clay: the pits were sunk there for the good reason that no surface material had to be removed before the clay could be extracted.

'Alom Rock' is first recorded in 1718. If it did in fact refer to a large fragment of alum-shale thereabout, this was presumably another of the ice-borne erratic boulders which used to litter the Birmingham area. At the base of the northern end of the ridges is an irregular strip of Keuper Marl, below that are gravelly river terrace deposits, and a broad band of alluvium has filled up the deepened post-glacial valleys. The Rea and Tame formerly wound aimlessly across this silty plain, whose gradient is very slight and washed over it after every rainstorm. (They flow now in gently curved deep channels that contain even the worst floods: the former loops and multiple courses have been infilled).

Keuper Marl is impervious to water, which it retains in its soggy topsoil, and with which its upper layers combine readily to make thick mud. Oak forest is the natural vegetation - we are, here at the northern limit of Arden - with thick undergrowth of bush and bramble, practically impenetrable except alongside the boggy streambeds.

Permeable drift is less favourable to oaks, which require vast quantities of water, and tends toward a natural cover of hazel, birch, broom, gorse, and grass, thinning out on the stoniest patches. A marshy valley floor is the province of willow, alder, reed, and tussocky grass. If we could have flown over the manors from the north, say ten centuries ago, we would have seen the ridges rising out of the flooded plains, a fringe of forest giants on their lower slopes, then the rounded tops with patchy heath and wood, backed by dense deciduous jungle climbing to the highest ground where it would begin to thin out.

These details of solid and drift geology are derived from the O.S. survey, 1852-1922, and listed sources. A few old names provide confirmation of our description of the natural landscape (Map 4). 'WASHWOOD HEATH' is a composite name: the WASH was the plain so often laved by floods, WOOD applied to the slope at its edge, and the HEATH lay above. Old gravel pits are shown on end-C19th maps north of Phillimore Road. ADDERLEY WOODS lay along the south bound, SHAW (little wood) HILL was at the drift edge. Along (Cherry) WOOD LANE were OVER and LOWER WOODS. NEW LAYS (leys) near Garrison Farm indicate late clearance of timber, as do NEW LANDS south of Alum Rock.

BLAKE LANE refers to a bleak spot, as it must have been after deforestation. BULLS WOOD and a close called HURST are found on the clay of Little Bromwich. In Ward End Park we find the SLADE (which gave its name to an open FIELD), the boggy valley in part of which a pool has been made. WASH BROOK well describes a stream noted for its fast run-off from the high clay once the water-retaining wood had been cleared. Land above Saltley Mill was doubt-less well called WET MEADOW, lying as it did beside two arms of the Rea.

Beside the watercourses are found the MOORS or bogs: DRIFT HOLMES indicates flood-meadows just below the drift terrace. CONEYGRE means 'rabbit warren' and that means sandy ground for dryness and easy burrowing. Doubtless many other revealing names have disappeared along with the landscape they described, but enough survive to authenticate our picture of it. One would like to know the origin of GARBIDGES, if only to re-assure the Ideal Villagers who live thereon today.