Introduction to Conifer ID

ID of Conifers is a large and complicated subject, but I recently lead an informal Intro to Conifer ID botany  outing which was very well received.

I'll be doing it again in the New Year, but for the benefit of  iSpotters who don't live in South Oxfordshire (!) here are the basics. Do bear in mind that this is a simplification of a complicated subject!

Before we start, if you wish to learn about conifer ID you really will need a hand lens - a x20  is best, but a x10 will do if that's what you have. They only cost a few pounds for the normal folding type, and the advice to hang it round your neck on string or ribbon really is a good one - it may feel a bit geeky, but if you don't, sooner or later you will put it down in the long grass and lose it. Ask me how I know.. yes, I did it.

And you have to remind yourself of the First Rule Of Botany, which is "Common Names Are Misleading". Closely followed by "and the proper or scientific names keep changing - no use grumbling about it, just deal with it".

Right, here we go.

When we look at trees in general, we split them into two types - they are either Broadleaf or Conifer.

Broadleaf trees have - as you would guess - mostly wide leaves, mostly with veins in a net formation. Conifers have linear leaves: the veins run parallel along their length.

Some people  prefer to call them Deciduous and Evergreen.

Like everything in Botany, its not quite that simple:  some Conifers are deciduous (Dawn Redwood, and Swamp Cypress for example) and some Evergreens are not Conifers - Holly, for example, or Box.

 But it will do for a start.

So, Winter is a good time to look at Conifers/Evergreens, as they are (generally speaking, allowing for the exceptions mentioned above) the green ones, making them easier to spot.

When we look at Broadleaf trees in summer, our first point for an ID is the arrangement of the leaves - are they opposite or alternate?

When IDing conifers, we don't initially look for the arrangement, we firstly look for the type of leaf.

Conifers have three types of leaf  - needle, flat, or scale.
(As always, this is a simplification, but you have to start somewhere)

Needles are, as the name suggests, round and pointed. Pine are the obvious ones.
Flat leaves are generally long and thin, but are flattened - Yew would be the most familiar one.
Scale leaves require a hand lens to see clearly - things like the infamous Leylandii have scale leaves.

So the first thing you do is look at the foliage, and decide if it is a needle, a flat leaf, or a scale leaf.

Group 1) Needles.

These are needles - long and thin.

When looking at needles, the first thing is to count how many there are in each bundle.

Check several bundles to ensure you didn't pick an aberrant bunch... they are generally found in 2s, 3s, or 5s (these are all Pines or Pinus) or in clumps of 10 or more - which means Larch (Larix) or Cedar (Cedrus).

So already you have learned an easy ID trick: if confronted with needles, if they are in bundles of 5 or less, you can say with confidence "it's a Pine."

If in 10 or more, is it Larch, or is it Cedar? In winter it is easy to tell - Larch are deciduous, Cedar are not. So if the ground underfoot is covered with dead needles, and you had trouble finding a branch with any good foliage on it, it's Larix. As a broad generalisation, Cedars are stately, shapely trees, often planted in gardens or parks as individuals. You rarely find Larch all alone - it's a cash crop, fast-growing, so it's usually found in plantations - rows and rows of them all together. In addition, Larch have small cones, which tend to stick to the branches even when the needles have fallen, plus they have a habit of shedding branches, so in a Larch woodland, you will usually find plenty of twigs and branches on the floor, all with a number of small cones still in place.

Cedar, on the other hand, have large oval cones which do not fall - they shatter over time, on the tree, so you hardly ever find a compete Cedar cone, you normally only find individual scales:

Group 2) Flat leaves.

Long and thin, but flattened. They usually have two lines of whiteness underneath - these are stomatal bands, or bands (stripes) of stomata, which are the pores through which a leaf breathes. They often show up as silvery against the green leaf, but as so many Conifers have them, they are not all that much use in ID.

This group includes the familiar garden Yew, the exotic Redwoods, the less-familiar Tsuga, and everything we think of as a Christmas Tree,  including Firs (Abies) and Spruces (Picea). It also includes my personal favourite, Douglas Fir, which is not a Fir at all. More of that later.

Picea omorika - Serbian Spruce

This is a hand-lens close-up of Picea omorika or Serbian Spruce.

As you can see, long thin flat leaves, and lots of white stomatal bands.

The way the leaf is attached to the stalk is a major factor in IDing this group of Conifers, so we will look at that in more detail later.

So far, I have not been able to come up with a catchy name for Conifers in Group 2, so if any of you out there know of something, do let me know, otherwise I shall have to make something up, and that is simply "not done" in botany.


Group 3) Cupressaceae.

There you go, a nice new word for you to learn. Koo-press-ay-cee. Think about the "press" part of the name, as it contains the clue to this group - it's those with scale-like leaves, or leaves which have been "pressed" against the stem.

As mentioned at the start, it's a generalisation, but the term Cupressaceae can be taken to cover most of those Conifers that don't have either needles or flat leaves. This means (she said with a straight face) that you can look through your hand lens at the foliage and say, solemnly, and instantly, "It's a cupressaceae"  which will impress all non-botanists. In fact, you can probably look at a conifer from about five paces, see that it's neither needled nor leaved, and say knowingly "Ah, looks like a cupressaceae from here, but of course without my hand lens I can't tell you exactly which one."

Here's a random selection from the internet:

As you can see, they are all somewhat flattened, the branchlets tend to be in one plane - pressed, you could say, Koo-PRESS-ay-ceee -  and the smallest twigs are almost rope-like.

At first, they all look the same, but once you start looking through your hand lens at this group, you will start to see the differences - honestly!

They are a difficult group - but some are easier than others, and some have a strange beauty all of their own, when viewed through a hand lens: here is a close-up of some Calocedrus decurrens or Incence Cedar.

Please note, as per opening statement, that this, along  with Thuja plicata or Red Cedar, is not actually a Cedar. Cedars are in the genus Cedrus, and they have needles... I know, I know, you just have to learn to call them by their proper names.

And these strange spiky-looking things, left, are actually common or garden Lawson Cypress, as seen and photographed through a hand lens.

Amazing, aren't they?

Well, that was the briefest of introductions to Conifer ID, explaining the three main groups or types of conifers. Having grasped that idea, we can now start our walk up to the conifer area (heh heh, secret location) to put it into practice.

We will be watching the ground as we go, to see what is fallen: cones and needles are usually very visible, and give us good clues as to what is above.

We look at the foliage and decide if they are needles (if so, how many), or flat leaves, or scale leaves. This gives us a head-start to know which genus the Conifer is likely to be.

And that is quite enough for one post - next time we will look at each of the three groups in more detail.

Digital microscopes...

Alyson was asking about Digital USB Microscopes, and would you believe, I actually have one.

One of those terribly embarrassing things where someone kind asks what what you'd like, you say "Ooh, ooh, a DUM please," they buy you one, you use it for five minutes, then put it in a drawer...

I've just dug it out again, and taken photos of a couple of leaves, both with the DUM and with my hand-lens-and-cheap-mobile-phone trick.

Item one: Common Lime leaf with nail galls.

Taken with DUM, which has its own built-in light.

2: same leaf, using hand-lens x20 and the light from the DUM.

Ah, I'm not actually in the same place on the leaf, so that's not a very good comparison, sorry, but it was so beautifully in focus that I felt I had to include it.

Focusing is a bit of an issue in both cases - more below.

 Right, same as top picture, the fork in the veins, one big one, one liddle one, not quite at the same angle.

Again, hand-lens, this time using its own in-built light.

 .

 This is a pear leaf with damage and browning, taken with the x20 hand lens.

This is the same leaf, with the DUM. Much better definition on the small veining.

Regarding focusing, each method has problems.

As mentioned in the Amazon review for the DUM, the stand it comes with is not particularly good. It would be a worthwhile investment to get a better one.

I found that you have to hold the body of the DUM in order to twist the focusing ring, then when you release it, of course it's not quite in focus any more. It takes a bit of practice to get it right, and it's a shame they don't have a mouse-operated digital focus for it.

The hand-lens is simpler, but again it's sometimes difficult to get the focus just right.

In both cases, I imagine that practice would make, well, if not perfect, then a lot better.

The DUM is advertised as being 10x -200x, but I did not find a way to select the magnification - it was more a case of twisting the zoom until the object became sharp. But I haven't used it for aaaaages and there might be more instructions on the CD that came with it.

Hope this helps!

Tilia crib for Pete

Hi Pete, *waves*

As discussed, the ID of Lime trees - Tilia -  is really difficult as they hybridise so freely. The books say that there are three main types: Common, Large leaved, and Small leaved, with Common being a hybrid of the other two. Plus a few more ornamental varieties, but I don't worry too much about those as they are not likely to be found outside of parks and aboretums. Arboreta? You know what I mean.Oh, and disregard the phrases "large leaved" and "small leaved" as the size of the leaves is NO sort of indicator, annoyingly!

Be warned, they continue to hybridise, so there are in fact a wide range of hybrids, all shading from closer to one, than the other. So they don't always fall neatly into their category.

Having said all that,  I made a crib, or Table of Differences, for Limes last year (or was it the year before?) which now seems a bit basic, but it might get you started on creating your own crib:

As you can see, very simple: it's not a key, simply a collection of relevant ID points all in one place, for the three main Limes plus the one that I've encountered locally - of course, you are most welcome to add as many other species as you wish, I restrict mine to commonly occurring species, in order to keep them down to A6 size for my  famous Botany Cribs pack  (which certain members of the Midweek Botany Crew keep trying to steal). They usually start out hand written, but after an Incident on a rainy day, I decided to copy them all onto spreadsheet format, so that I had a permanent copy at home.

This has proved to be a very good way of doing it: I print them out and stick them onto the index cards, I can then annotate while out in the field, then at home I update and reprint every so often. And when they get too wet to read, I just print off new ones.

Here's my battered pack:

Hope this gets you started - the idea is that you fill in any gaps, and add more features as you discover them. Obviously I don't bother with any features that they all share, just in features that help to differentiate.

When you come across a tree that doesn't quite fit any of the categories, then you have to turn to the reference books, but at least the crib can cut down the number of times you need to do that.

Have fun!

Hello, iSpotters!

I live in South Oxfordshire, and I'm a Professional Gardener, Horticulturalist and Botanist, competent at IDing garden plants, trees and shrubs, and pretty much all of the vascular plants found in woodland settings.

Wild flowers, however, were something of a closed book to me, until a couple of years ago, when I started getting interested in them as well. Up to that point, professionally, they were all just "weeds" and to be dealt with in a particular manner.

However, I'm now extending my ID skills to include wild flowers. This has meant a whole heap of wandering around lonely fields and hedgerows with a reference book and a hand lens.

I belong to the Oxford Botany Email Loop, a loose collection of botanists in and around Oxford, who meet up from time to time to carry out surveys, or just for the pleasure of botanising.

Over the past few months I've also been introduced to iSpot, which is a fantastic resource for plant ID. I find that I sometimes struggle to make an ID from a photo, especially when the photos are not very clear, or don't show the parts of the plant that I need to see. But it's very good practice, and it's nice to be able to share knowledge: there are some fantastically knowledgeable people on iSpot, and they are all very happy to explain  and encourage.

One quirk of iSpot is that they don't have a chat facility, and they don't allow individual messaging, so I've created this resource to allow people to contact me by email, at Rachy.Ramone@gmail.com if they want to.

I've also taken the opportunity to create three Helpful Hints pages for making better iSpot Observations, and I hope that you find them interesting and helpful.