Exploring the month of April and the behaviour of its trees

APRIL was the second month (March came in first) in the 10-month Roman calendar. It is the fourth month in the 12-month sequence of our modern Gregorian calendar, named after Pope Gregory XIII, who introduced the time-scale in 1582, but what are the origins of the word April? Theories abound, including that it is rooted in the Latin word Aprilis, which is derived from the Latin aperire meaning ‘to open’. This appears to reference the re-foliation and blossoming of trees, which begins in earnest in April in the Northern Hemisphere. 

READ MORE: Spring: How trees tell the arrival of new season

April is a magical month, with writers, poets and painters certainly portraying it that way down the ages. Some have even dedicated a work to the month, such as London-born Victorian poet Robert Browning.

O, To be in England
Now that April’s there,
And whoever wakes in England
Sees, some morning, unaware,
That the lowest boughs and the brushwood sheaf
Round the elm-tree bole are in tiny leaf,
While the chaffinch sings on the orchard bough
In England—now!
From ‘Home Thoughts, from Abroad’ by Robert Browning (1812–1889)

It’s interesting that Robert Browning wrote this poem while abroad in northern Italy. As someone who has spent long periods away from England I can testify to how nostalgia invariably sets in during the month of April.

“Spring wakens too: and my regret becomes an April violet” (Alfred, Lord Tennyson). (Image: FJ)

Alfred, Lord Tennyson gave April the same prominence in his writings, albeit with an expected melancholy style.

Now fades the last long streak of snow,
Now burgeons every maize of quick
About the flowering squares, and thick
By ashen roots the violets blow...
From land to land; and in my breast
Spring wakens too; and my regret
Becomes an April violet, 
And buds and blossoms like the rest.
‘April’ from ‘In Memoriam A.H.H.’ by Alfred, Lord Tennyson (1809–1892)

All that said, there is a darker side to the month of April. Trees and other plants are now out of winter dormancy and growing rapidly, but those who grow plants on which they rely for food have historically had an altogether different take on the month.

I recall a comment made by my uncle over six decades ago. It was early April and we were sheltering in his allotment shed. The plum and pear trees were covered in blossom, daffodils were out and the sky was black and sunlit at the same time, while hailstones hurtled down. 

“April is the meanest month, lean times,” my uncle quipped. He was referring to the fact that all the winter greens had gone and his store of root vegetables and potatoes was almost bare. And it would be two more months at least before this year’s crops of broad beans, garden peas, new potatoes and strawberries could bear fruit. April would definitely have been a time of want for his father (my grandfather) 40 years before that.

Primrose, which gets its name from the Latin Prima Rosa, meaning the first rose of spring. (Image: FJ)

My uncle clearly had that psyche.

OPEN SESAME

That apart, April is a month of swift and sure movement. There are four facets to the regrowth of trees in spring, with the biggest spurt in April. They are: germination of seed and the establishment of tree seedlings; bud burst and re-foliation; extension growth, and flowering. 

Of course, flowering will essentially be done for some tree species before April (e.g. sallow, common hazel and common alder). Trees like rowan and whitebeam will break into blossom in May and others like sweet chestnut and dogwood much later. Nevertheless, April is the main flowering month for the majority of the catkin-bearing members of the birch and beech families (silver birch, beech, oak and hornbeam) and the bulk of the blossom-bearing Rosaceae (gean, crab apple and wild pear). 

Anyone wanting to delve into the mysteries of trees at this time of year will need a collection of texts from a time when study into the intricacies of tree seed germination and bud burst was all the rage. Use them to backup and authenticate your own modern-day observations.

I continue to rely on a relatively small number of naturalists, botanists and science writers who were active during the latter part of the 19th century and through the first several decades of 20th century. Two in particular worth mentioning are Edward Step and Gertrude Clarke Nuttall.

IN THE BEGINNING

It all starts with seed and a seedbed, viable seed and substrate conductive for seed germination, tree seedling establishment and growth. The ‘birth of trees’ is how Gertrude Clarke Nuttall put it in one of her classic treatises.

“Nothing makes one realise the continuity of history so clearly, or links up so effectually the past with the present, as to stand by some great living thing and picture the days when it was born, for it alone stands as the living witness of the long passage of time,” she said.

“Loveliest of trees, the cherry now, is hung with bloom along the bough, and stands about the woodland ride wearing white for Eastertide” (A.E. Houseman). (Image: FJ)

For me, looking at the germinating acorn in the hedgerow outside my house, I can’t help imagine what the neighbourhood will look like when that tree is the age and size of the one ten yards away – a 200-year-old Quercus robur

HEARTS OF ACORNS

So let’s start with oak, which is born from a nut inside which the parent tree has stored up sufficient food for its offspring to feed. This is during that difficult time from the first split in the acorn until the new roots are firmly embedded in the soil. Acorns are anxious to go straightaway, unlike the deeply dormant seeds of the hawthorn which may have been spawned in the same hedge. This is a very likely scenario too, because English oak does not readily germinate, establish and regenerate under its own shade inside the woodland. Acorns germinating in April, going on to successfully establish oak-tree seedlings and saplings, are more likely to be found at the base of the hedge or the edge of the field, having fallen the previous autumn from a hedgerow oak tree. 

That first split in the shell comes at the end of the acorn away from the nut’s big scar and reveals a minute tunnel along which creeps the fine white first root, anxious for the damp earth. The first shoot follows on, growing strong, sturdy and tall. This early growth is fuelled by food contained in the seed leaves, but they are not also the first foliage leaves, as would be the case in beech. They are simply the two halves of the acorn swollen with starch for the embryonic plant to feed on until the first true leaves, the foliage leaves, are formed.

Once the first true leaves are in place, the seed leaves will begin to dry up and shrivel as last year’s reserves run out, and new energy created from this year’s late-April sun takes over. This is only the start of a very long haul for the English oak tree: “Three centuries he grows; and three he stays supreme in state, and in three more decays” (Dryden). 

BEGINNINGS FOR BEECH

Warmed by the early spring sunshine and watered by April showers, triangular-shaped beech nuts scattered amongst the dead beech leaves start to swell. Cracks in the three-sided shells form, through which appear the tiny white roots. They know exactly where they want to grow because whatever the position the nut is laying, its very first root re-orientates, turning downwards to penetrate the ground. 

There follows a white shoot which similarly turns up to the light. A pair of leaves grow out from the top of the shoot, folded to look like the closed wings on a butterfly. Within no time at all, the leaves have parted and spread. And there, poised on top of the white seedling stem, is a lovely leaf butterfly, shiny dark green above and gleaming silver beneath, soaking up the spring sunshine just like the real thing – the peacocks, commas and red admirals – when they emerge from hibernation in spring. 

Germinating beech seedlings pushing up through the deep leaf litter. The seedling on the right has its pair of so-called ‘seed leaves’ likened by Gertrude Clarke Nuttall to a pair of butterfly wings. The seedling on the left is slightly more advanced and bearing the first pair of true beech leaves. (Image: FJ)

These are also so-called seed leaves, but unlike those of oak, which stay in the acorn to supply food, these leaves are the first foliage leaves to trap light and make sugar for fast early growth.

LEAF BUDS AWAKE

Seeds are germinating on the woodland floor, but up above in the canopy, leaf buds are breaking. Only when the first hint of green ripples appear along the bare branches is spring’s sweet call clearly heard, says G. Clarke Nuttall in yet another of her masterpieces on trees and their life story, this one entitled The Awakening of the Leaf Buds. 

Throughout winter’s short, dull days and long, cold nights, the buds have been at rest while preparing for spring. Urged into action by light and warmth, each, in its own way and time, gives birth to the embryonic leaves protected by tough, waterproof and insulating bud scales during the winter months. Each and every tree species has its own particular avenue to re-foliation, but one is of particular interest. Like English oak and common beech, it too was a famed feature of mixed deciduous woodland.

WHICH ELM?

When G. Clarke Nuttall put pen to paper back in the 1920s, the English landscape was covered with elms, but apart from some lucky pockets like Brighton and Hove, these have all but disappeared. However, we still have wych elm (Ulmus glabra) and, according to Nuttall, what I am about to describe was always best seen in wych elm, even when English elm predominated.

Elms burst into green very early in spring, when the clusters of red flowers were finished, and became covered with the palest green rosettes. Some think these are the elm tree’s leaves, but they are in fact tiny fruits already formed in the centre of a green wing to aid dispersal. This all happens in March, but the ground will soon be littered with winged fruits which dry up to be whisked away by the wind. 

For the shortest time, wych elm trees revert to being bare, but other buds, the leaf buds, have been swelling and lengthening. Come April, leaf buds are bursting forth with bunches of pleated leaves which droop from the buds. These so-called ‘pleatings’ open into separate leaves (stalk-less in the case of wych elm) and the once-bare branches are soon dressed with exquisitely green leaves, now in positions best suited to interception of the sun’s rays.

A germinating acorn which could be on its way to 1,000 years? (Image: FJ)

An old saying uses the size of the growing elm leaf as the countryman’s guide for the sowing of spring barley:

“When the elmen leaf is as big as a mouse’s ear,
Then time to sow barley never fear,
When the elmen leaf is as big as an ox’s eye,
Then say I, ‘Hie, boys, Hie.’” 

What follows is the race to put on as much extension growth as possible before the cooler months come round again

THE CRUELEST MONTH

You’ll have to excuse me for ending on a somewhat sad note, for amongst all the joys of April lays a piece written by a poetic icon.

April is the cruellest month, breeding
Lilacs out of the dead land, mixing
Memory and desire, stirring
Dull roots with spring rain
Winter kept us warm, covering
Earth in forgetful snow, feeding
A little life with dried tubers 
‘The Burial of the Dead’ from ‘The Waste Land’ by Thomas Stearns Eliot (1888–1965).

My own skills are woefully inadequate to decipher the poem’s actual meaning, but the common thinking among experts is that T.S. Eliot is recalling the transformation of the innocent pre-WWI world and grieving as Europe becomes a place of hopeless decay.

Perhaps my uncle’s view of April had nothing to do with empty apple stores and potato sacks, but was informed by reading T.S. Eliot. Perhaps significantly, as a young boy he had lost two uncles in France, little more than 10 years older than he. Regardless, there is a connection in the last line of Eliot’s poem (‘A little life with dried tubers’), which refers to the ‘fag end’ of the potato store.