Here and there in this region on the edge of the Chilterns the soil consists of marl – a mixture of clay and calcium carbonate which was formerly used as fertilizer. The marl was dug with spades and wheelbarrows and hauled away on horse-drawn carts.
The abandoned pits can be encountered almost anywhere in the countryside. Most are fairly small, no more than fifty or sixty feet across and twenty or thirty deep. Sometimes they are used as tips for broken washing machines, rolls of rusty barbed wire, milk crates, and similar debris. Occasionally they are put to more ingenious use. The golf course green nearest the Iron Bridge in Cassiobury Park, for example, lies at the bottom of an old marl pit, the green itself thus hidden from the golfers on the tee.
In places that pit slopes pretty sharply; as children we used to toboggan there. Other depressions, a few as large, may be found nearby in Whippendell Wood.
The marl was first dug at about the time, a couple of hundred years ago, when the grand landscapers were at work transforming the parks of the wealthy. This was also the heyday of the great furniture makers, whose factories at High Wycombe had an almost insatiable demand for hardwood. These factors combined to ensure the widespread planting of beech – a noble, imposing tree for planting schemes both formal and otherwise, and a valuable source of first class timber.
The grounds and park attached to Cassiobury House are now reduced to a fraction of their former size. In what remains – the present Cassiobury Park, the adjoining golf course, and especially in Whippendell Wood – evidence of this beech-planting can everywhere be seen.
For such a large tree the beech is not long-lived. After two centuries – a mere seventy or eighty thousand dawns – some of the planted specimens are piecemeal beginning to die. They are apt to shed a large bough without warning; it can be dangerous to linger too long underneath.
On the higher and sloping ground in particular the beeches have reached their best. In maturity they are massive, smooth-boled monsters with elephantine limbs and silvery-grey elephantine skin, sometimes bearing scars. A hundred pellet holes from a wanton shotgun blast, unleashed perhaps by a poacher who prowled the woods before any of us were born, have each expanded to the size of a ten-pence piece – or a florin, as he would have called it. The carved hearts and initials of forgotten lovers, expanding steadily with the years, have become indecipherable. One tableau has been so altered by the tree as to resemble the secret markings on some Druid stone, forming the face of a deity: the pagan protector of all things in the woods, not least of them the beech.
The beech nuts, or beech mast, are sometimes, as in this last autumn, shed in such prodigious quantities that they sound like rain in the days and weeks of their fall. They form an important source of winter food for many animals and birds; the population size of such species as great tit and chaffinch can be related directly to the abundance of the mast crop.
Each nut is quite small, half an inch long or so, of a pattern called by botanists “triquetrous”, with three sharp-edged sides and a small rounded base. It opens at the tip in spring and there emerges a creamy white radicle which pushes down into the soil.
Competition among the seedlings is so intense that each has less than one chance in several hundred thousand of reaching maturity. The adult trees blot out the light, spreading a canopy a hundred feet or more overhead, and in the autumn send down a blizzard of leaves which, slightly toxic, inhibit undergrowth of any kind.
Only where a large tree has fallen, or where the ground has been otherwise cleared, do the saplings stand a chance. Then the race is on: the first up to the light is the winner, and the rest are left to die.
This may be seen plainly at one of the old marl pits in Whippendell Wood. Digging there must have been abandoned about a century ago and the soil left to its own devices. Surrounding the pit are veterans of the planting era; at the very edge are several whose roots have grown in a tangle down the slope. These trees are the parents of those that have sprung up in the pit itself.
The young beeches began with a handicap. Some have as much as thirty feet to make up before even reaching ground level. They have grown fast, with smooth, clean trunks, not wasting time or effort on producing limbs. Everything depends on reaching the canopy.
But the older trees have already taken the opportunity of spreading their branches further and further into the gap, greedily consuming the free space. Only one or two of the young beeches in the middle of the pit have any hope left. When existence itself is the prize, even these silent grey leviathans care nothing for their offspring.