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Now that the deciduous leaves are down, it’s a good time to think about the Gymnosperms (the conifers and their allies). Most of them are evergreen, of course, but the deciduous ones can be quite challenging to identify in winter. I’ll start with an overview.
We’ll cover all of the genera from the most familiar, like Scots Pine and Yew (on the right), to some you may not even have heard of, like Keteleeria (main)
It’s very clear that some people like conifers much more than others do. I’ll concentrate on the species that you are most likely to see as you walk around town: as street trees and in parks, cemeteries and so forth.
If you’re really keen you’ll plan a trip to Bedgebury National Pinetum (Kent, left) or Westonbirt Arboretum (Gloucestershire, right) before the winter is over.
We’ll begin with a quick run through of the easy and distinctive species for completeness sake, before spending time on the big, more difficult genera like Pinus, Picea, Abies and Cupressus. The easiest of all is Araucaria araucana (Monkey-puzzle, Araucariaceae) from Chile
The most conspicuous you’ll encounter is Wellingtonia (Sequoiadendron giganteum; Cupressaceae, formerly Taxodiaceae), the Giant Redwood from California. The top branches will often be bare as a result of lightning strikes.
On the right of the last tweet is Wellingtonia Avenue in Berkshire, running up from Wellington College to Finchampstead Ridges. Despite their massive bulk, very few of these trees blew over or snapped in the great storm of October 1987.
The other California redwood, Sequoia sempervirens, is seen less often. From a distance they are rather similar, but close up they could hardly be more different: Wellingtonia (left) has Cypress-like scale leaves, but Sequoia (right) has separate needles like a Yew.
Their bark is superficially similar but Wellingtonia is more platy (left) and Sequoia more stringy (right). Both are soft enough to punch if that's how you're feeling.
The 3 cedars are easier to tell apart from a distance than they are from close-up. Cedar of Lebanon is the tree you expect to see on the approach to any stately home. It has dark leaves, horizontal branches and level shoot tips (think “level = Lebanon”). Huge, upright cones.
Deodar (Cedrus deodara) has narrower, bright green needles with shoot-tips that point downwards (think “droopy = Deodar”)
You are most likely to see Atlas Cedar as the cultivar Cedrus atlantica ‘Glauca’. This has very pale blue, almost silvery foliage, and shoot tips that point upwards (think “ascending = Atlas”)
Smell is a very useful way of telling different Cypresses apart. When crushed, the leaves of Thuja smell sweet, like fruit-cake (left), while Chamaecyparis foliage smells bitter, of resin and parsley (right).
The two commonest Cypresses are told apart by their leading shoots: droopy in Lawson’s (left) and straight upright in Leyland (right).
Of course, this trick doesn’t work if they form a hedge that has been trimmed (well-trimmed Lawson's, left). These are the dreaded hedge plants from hell, that are the cause of so many neighbour disputes (untrimmed Leyland often gets much too big, right)
The genus Cupressus has some very familiar species: the pencil thin C. sempervirens (left) will remind you of Mediterranean graveyards (aka Funeral Cypress), and the light-blue-leaved C. arizonica var. glabra (right) is very common in parks in town.
The distinctive thing about the true Cypresses (the old genus Cupressus) is their cone. They are big, spherical and look like poorly inflated footballs (left). The cones of Lawson's are much smaller (right; formerly Chamaecyparis) and roughly woody.
The 2 deciduous redwoods can be tricky to tell apart in winter unless you can find fruits (binoculars useful here): these are stalked in Metasequoia (left) but sessile in Taxodium (right). Metasequoia is much more commonly planted as a street tree in towns.
Two important genera get invited indoors at this time of year. Old fashioned Christmas trees were Norway Spruce (genus Picea, left); modern ones are Nordmann’s Fir (genus Abies, right). Much more detail about the distinction between Picea and Abies later.
The other deciduous Gymnosperm genus is Larix (the Larches or Tamaracks); they have their needles in bunches (left), a bit like a cedar, and conventional Pinaceae cones (right).
There are only 3 native Gymnosperms in the British Isles: Scots Pine (main), Yew (TR) and Juniper (BR). The British species are easy to identify, but pines (genus Pinus) and junipers (genus Juniperus) are species-rich and can be challenging to identify to species (see later).
That's it for the introduction. I'll start a new tweet for the more technical stuff about identification. We'll start by looking at the differences between the Gymnosperm families, then go on to consider the genera in each family.
