Laudator Temporis Acti

Richard Wilbur, March:

Beech leaves which might have clung
Parching for six weeks more
Were stripped by last night's gale
Which made so black a roar

And drove the snow-streaks level.
So we see in the glare
Of a sun whose white combustion
Cannot warm the air.

From the edge of the woods, in gusts,
The leaves are scuttled forth
Onto a pasture drifted
Like tundras of the north,

To migrate there in dry
Skitter or fluttered brawl,
Then flock into some hollow
Like this, below the wall,

With veins swept back like feathers
To our prophetic sight,
And bodies of gold shadow
Pecking at sparks of light.

In botanical terminology, the adjective that describes the beech leaves in the opening lines of this poem is marcescent, defined by the Oxford English Dictionary as "Of a part of a plant: withering but not falling off." The corresponding noun is marcescence.

See Gale Lawrence, A Field Guide to the Familiar (1984; rpt. Hanover: University Press of New England, 1998), p. 76:

You can also recognize a beech tree from a distance because of its tendency to hang onto some of its leaves through winter. Most deciduous trees completely separate themselves from their old leaves by forming a layer of wound cork—called an abscission layer—where the leaves had been attached. The leaves then fall of their own weight or are knocked off by rain and wind. Oaks and beeches don't form complete abscission layers, so some of their dead leaves hang on until next year's leaves push them off. Winter beech leaves are papery, light tan, and sound like wind chimes in gentle breezes. Oak leaves, in contrast, are thick, darker brown, and sound merely like rustling leaves.

Robert Frost also mentions the same phenomenon in the second stanza of his poem Reluctance:

The leaves are all dead on the ground,
Save those that the oak is keeping
To ravel them one by one
And let them go scraping and creeping
Out over the crusted snow,
When others are sleeping.

In the final stanza of March, Wilbur probably alludes to the ancient Roman practice of divination by observation of the pecking of sacred chickens as they eat grain. See Jerzy Linderski, in Imperium Sine Fine: T. Robert S. Broughton and the Roman Republic (Stuttgart: Franz Steiner, 1996), p. 180 and note 140 on pp. 180-181:

The commanders in the field employed before battles the auspicia pullaria, divination from the eating behavior of sacred chickens, the pulli. The pullarius, the keeper of pulli, was a constant and ubiquitous attendant of the magistrate; and on imperial reliefs there appear occasionally representations of the pulli, pecking on the ground, or kept in the cage, the cavea.<sup>140

140</sup> On the pulli and the pullarii, see esp. Cic., De Div. 2.71-74 (and the commentary ad loc. by A.S. Pease, M. Tulli Ciceronis De Divinatione Libri Duo [Urbana 1920-23, reprint Darmstadt 1963]); Livy 10.40; 41.18.14; Dion. Hal., Ant. Rom. 2.6.2. Two pulli, feeding, are represented on a third century bronze ingot, RRC 1.133, no 12, but they are perhaps connected with the Dioscuri (Crawford, RRC 2.718, n. 2). On the altar from the vicus Sandalarius, the new augur Lucius Caesar holds lituus, and a pullus at his feet is pecking at something, thus denoting the tripudium (I. Scott Ryberg, Rites of the State Religion in Roman Art [= Memoirs of the American Acedemy in Rome 22, Rome 1955] 60-61, and pl. XVI, fig. 31). For further references, see Zwierlein-Diehl, "Simpuvium" (above, n. 118) 409-413 (and pl. 79, 3-4). For a military pullarius, and the image of the pulli in a cage, see A. von Domaszewski, Die Fahnen im römischen Heere (= Abhandlungen des Archäologisch-Epigraphischen Seminars der Universität Wien, Heft V, 1885) 31-32.