Prothonotary Warbler

Prothonotary Warbler

Saturday, 18 March 2017

Winter photography

The title might conjure up snowy landscapes and such, but this post will be about a different type of winter photography.

I am involved in a project which in part, involves getting photos of twigs of trees and large shrubs, focusing especially on buds, leaf scars and other characteristics that are helpful in their identification. I must admit before this I had never spent a lot of time using such minute characteristics to identify trees. Instead I would consider the type of habitat the tree was growing in and rely on its overall form, as well as the bark characteristics. So this project was a challenge, especially since it relied on a fairly precise form of macro photography. I've explained a little about my macro technique at the end of this post.

I'm not sure exactly how many I have photographed so far, but well over one hundred species. This has involved a lot of time looking through the camera, as well as countless hours processing the images afterwards. But it has been an eye-opener in some ways.

Lots of the buds and leaf scars are extremely small, and at first glance one doesn't look a whole lot different than another. But a closer look just highlights the tremendous diversity there is. This first one is Black Maple, an uncommon tree in Canada limited primarily to southern Ontario. It has fine gray hairs on the cluster of terminal buds.

This next one is Ohio Buckeye. For all intents and purposes it is an endangered species, although not officially so. It occurs naturally at only one location in all of Canada.
A somewhat similar species, at least in the same genus, is Horse Chestnut. It isn't native to Ontario, but is sometimes planted for ornamental purposes. Even though it is the same genus as the previous one, the bud and leaf scar are quite a bit different.
This next one does not have any legal status, although it is extremely rare in Ontario. It is known as Pawpaw, and at least from the historical data, is more common in Chatham-Kent than any other municipality in Ontario, which is a bit surprising given the overall lack of forest cover in C-K.

Next are a few of the hickories found in Ontario. First up is Bitternut Hickory, fairly common in southern Ontario deciduous woods. It is readily identifiable with its bright yellow buds.
 Next is Red or Pignut Hickory. It is quite rare in Canada, being found only in a small part of Essex County and several municipalities from about Long Point east to the GTA.
 Big Shellbark Hickory is scattered across an even smaller part of extreme southern Ontario than the previous species. A telltale feature is that this time of year, many of the leaf stems remain attached to the outer twigs.
 Much more common across southern Ontario and Quebec is Shagbark Hickory.
 These next few are shrubs. First is Flowering Dogwood, an endangered species in Canada. This first image of it shows the non-flowering buds.
 The flowering buds are quite large by comparison, and in late April or early May will open up into an impressive white 'flower', although what appears to be white flower petals are really sepals, another part of a flower, and the petals themselves are very tiny.
A common shrub especially in damp places is Red-osier Dogwood. In the winter its stems are quite bright red, as shown.
 An uncommon shrub is American Hazel, most often found in shrubby prairie, savanna and even drier rocky habitat. These are the male flowers that will open in the spring.
 Not a native species, but occurring in natural areas from time to time, is Winged Euonymus, which has prominent wings along its stem. Not all are as prominent as what shows in this next photo.
 A related, native Euonymus is Burning Bush, which has somewhat square branches.
Ash trees are on the decline in southern Ontario. For more on that topic, check out this previous blog post. This first image shows the terminal buds and twig characteristics of Black Ash, which occurs in quite wet habitat.

In comparison is Red Ash, with its densely hairy stem. It is, or at least was, one of the most common ash species in southern Ontario.
 A real rarity is Blue Ash, found in a few scattered locations in southern Ontario. It has declined due to the Emerald Ash Borer, and is getting harder and harder to find even where it formerly occurred. It is easily identified by its winged stems.

A cross-section of a Blue Ash stem
Another rare and declining tree is Butternut, legally endangered due to a canker that has killed many individuals.
 Closely related is the much more common Black Walnut.
 Next is English Walnut, not native but occasionally planted in landscape settings. The green twig is clearly distinctive.
The unofficial flagship tree species of the Carolinian Life Zone is the Tuliptree, with its distinctive buds.
 Hop Hornbeam, shown next, is identifiable as its partially developed male flowers are present throughout the winter.
Oaks are plentiful across the Ontario landscape. Their buds and twigs aren't always that distinctive, but in these next two examples I show White Oak, with its reddish, hairless twigs.....
 ....and Swamp White Oak, with its somewhat shaggy twig.

An extremely abundant shrub across southern Ontario, is Staghorn Sumac. Its twigs are densely hairy.

Another shrub is Wayfaring Viburnum, native to Europe but commonly planted  for ornamental purposes and as a food source for birds. The leaf buds are very different from almost every other species I have seen so far.
 Prickly Ash is not something one wants to go charging through at any time of year. The thorns are quite stout. The thorns in combination with the leaf scar bundles almost looks like a face, with arms outstretched.

And last, but not least, is this next one: Cherry Birch. It is native, legally endangered, and limited to one site in all of Canada, in the Niagara peninsula.

These are just a few of the many twigs and buds, etc that I have photographed over the last few months. It is a laborious task, but enjoyable, and I have been able to work with some really keen botantists and horticultural specialists in the process. Many of these photos were taken from specimens from the University of Guelph Arboretum, and I have lots more to do!

All of the above photos were taken with a full frame camera, a 100mm macro lens, and up to 68mm of extension tubes. Even at that, some of the photos were cropped. Almost all are at life size or more, although the photos as shown here are actually much greater than life size. The depth of field at this magnification is extremely shallow, in some cases only a couple of millimetres, so I have had to use flash, as well as a flash diffuser. I have also had the camera set-up on a tripod with a ball head, and a focusing rail which enables me to fine tune the focus to fractions of a millimetre.

So next time you are out hiking or birding during the leafless season, take a moment or two to explore and enjoy the interesting examples of nature's design all around you, including twigs. You might have to reverse your binoculars and use them as a magnifying lens to see some of the features.












9 comments:

  1. Great post! Winter tree/shrub id is something I have yet to put any serious time into

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    1. Thanks, Reuven. I used to do a bit when I was working at Rondeau in the 1970s and early 1980s, but had gotten away from it for the most part until this latest project came along. There are just too many things to keep track of across the natural landscape!

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  2. Really interesting collection of pictures. I must try a little harder!

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    1. Thanks Furry Gnome...I see on one of your latest blog posts you have been doing something similar. It is a challenge, isn't it!

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  3. Fascinating post and lovely photos, Allen. Thank you so much for sharing, and warm greetings from Montreal.

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    1. Thanks for your comments, Linda...glad you enjoyed it.

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  4. Great post and photos, Allen. Very inspiring. Last winter/Spring I took a great interest in finding and photographing buds, but this winter/spring. I've largely ignored them. Now I see what I've missed!

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    1. Thanks for checking this post out, Mark. I'm glad you enjoyed it. Depending on where you are located, there may still be time to get some of those twig and bud photos before the leaves start to emerge. I'm going to get out and get some more in the next few days.

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  5. I'm a bit south of you, basically in the middle of Essex County, 30 min from Point Pelee and 30 min from the Detroit River.

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