Warts and all

In a recent post (Cover up, 14th Jan.) I discussed how spines, hairs etc. help succulents conserve water. In some families we also come across plants where the leaves are (partly) covered in warts, papillae or tubercles. Although these are often highly decorative, it seemed likely to me that they would first and foremost serve a useful purpose. After doing a bit of research I came up with some interesting information.
It appears that the presence of these projections on stems or leaves has an advantage for the plants in that the breathing pores are hidden in the lower areas between them. This diminishes transpiration and protects the plants from dehydration.
In the case of warts, there is an additional advantage:  their epidermis is rich in crystals and lies over cells that store up tannin. This combination makes the plant rather unattractive to herbivores.

Crassula tecta is named after the warts on the leaves (tecta =covered or protected)

crascoramac2011_07_10#101_lznres - Copy
 Crassula corallina v. macrorrhiza (corallina = coral-like)

rhingran2010_09_12#009_lznres - Copy
In Rhinephyllum graniforme the genus name means file leaf 

hawoscabsca2009_11_29#008_lznres - Copy
Haworthia scabra is aptly named too (scabra = rough)

astrcorr2011_09_13a#048_lznres - Copy
This Astroloba used to be called A. aspera (=rough). The current name A. corrugata has a similar meaning (wrinkled or furrowed)

ruscmuri2010_09_05#038_lznres - Copy
Ruschia muricata is rough to the touch and that is exactly what muricata means

In the following two species the names make no reference to things like warts or tubercles, but it is clear that this is not because of lack of these.

aloispat_DSC0290_lznres - Copy
Aloinopsis spathulata

stomsuav2012-05-09#015_lznres - Copy
Stomatium suaveolens

Making simple pictures

The word simple has many meanings, but the ones I have in mind here describe qualities such as clear, clean, uncluttered,  not complicated or consisting of  only essential things.
Striving for these qualities may well be the most important way to get better photos. Andreas Feininger put it this way: “The simpler and more direct, the clearer and stronger the statement”.
The problem is that many of us tend to include as much as possible in the picture, so that the viewer easily gets confused, because there is no clear message. When there are fewer elements competing for attention, your picture will usually be a lot stronger. The first thing you have to do is decide what the main point of interest in the scene is. Then you must find out if there are any competing ones. If this is the case you must determine whether the image would become weaker or stronger by including these.  You may be able to do this on the spot, but it often easier to take a couple of different shots and select the best ones later on.  If you take pictures of plants in the wild, at least some of them should include a fair bit of the environment too.

One way to get a better, less cluttered picture is often to get closer to the subject. As the famous war photographer Robert Capa used to say: “If your pictures aren’t good enough you aren’t close enough”.
By getting closer you simplify the picture, thereby focusing attention on the main subject and getting rid of distracting objects.
Often the picture can also be simplified by limiting the Depth of Field

This picture gives a good impression of the harsh surroundings  this species of Hessea has to cope with , but visually it is not very appealing

The second picture gives much more information about the flowers, while still showing the plant in its environment

The first of these 3 pictures gives a good impression of what this species of Aloe looks like, but it is a bit jumbled

For the second picture I cleaned up the plant a bit, by removing remains of old leaves. This gives us a better view of the spotted backs of the leaves, which are so typical for this group of plants. By moving in, we have also got a much stronger picture

The third image verges on the abstract, but it is still recognizable. Because of that, it is not just visually but also botanically interesting

 greenhouse 043_lznresres
The individual flowers are quite beautiful, but the pictures does not show them to advantage

 greenhouse 048_lznresres
By going nearer I managed to get rid of the unnecessary and disturbing elements

Under cover; ways and means of conserving water

When looking at all those beautiful and unusual forms, colours and textures in succulents, it is easy to think that all thist is there  for our enjoyment.  I’m afraid  that is not the case; most of it is purely functional. For me, instead of  being disappointing, this fact  adds to my pleasure and admiration.  What can be more likeable than things that are both useful and pleasing to the eye? In this post we will have a look at some of the contraptions that succulents use to conserve water.
The one thing that sets succulents apart from all other plants is their ability to store water that they can use during periods when there is no external supply.  Obviously it is not much use to store a lot of water if you do not have the means to conserve it as well. Managing the stored water sparingly, mainly  has to do with reducing transpiration.
The rate at which plants lose water by transpiration is influenced by a number of factors: size and form of the plant, temperature, humidity,  intensity of sunlight, precipitation, wind speed, land slope etc.
On some days the temperature of the soil surface may rise as high as 75 degrees C, but a few centimetres higher up it will usually be much cooler  (up to 40 degrees less ). The two extremes will be separated by a layer of still air.
Comparable layers with gradients of humidity and temperature are found above plant surfaces; they have a great influence on transpiration. These layers are  disturbed or even destroyed by wind.  Because of this, many succulents have a cover of hairs, spines, etc. on the surfaces of their leaves or stems. This helps in producing and protecting these layers.  Such a cover  also gives a certain shade and helps to diminish exposure to strong radiation –especially when it is light in colour.  It has been found that tissue temperatures below spines of the cholla cactus (Opuntia bigelovii) can be reduced by as much as 11 degrees C.

In this Anacampseros albidiflora, short hairs on the leaves and long bristles between them, cooperate to keep the plant cool

Pelargonium barklyi is a tuberous plant. Although the leaves are short lived, it is apparently worthwhile to protect them with a cover of hairs     

Haworthia arachnoidea  gets its name from the spiderweb like cover of hairs. This variety is called scabrispina because the hairs are rough and hard like spines

In Senecio scaposus the leaves look like covered in felt

Many people think that spines are only there to protect the plants against browsing animals.  In line with what we have discussed here, I think that spines play a certain role in that respect too, but that it is not the only, or even the most important, one.


 In cases like Othonna euphorbioides (above) and Euphorbia stellispina  -and in many other plants- the spines are actually hardened remains of inflorescences




Leaf and stem surfaces are often thickened too, or coated with a layer of wax (Senecio stapeliiformis, on top) or cork (Othonna herrei)



Why do we take pictures?

That’s a bit of a silly question, isn’t it? We take a picture of something  because we want to have a picture of it. That’s all there is to it, or is it?
To get a more useful answer, maybe we should make the question less general: Why  take a picture of a certain plant?
The answer could still be vague: because I like to have a picture of this plant.  As long as that is all you want, fine. As they say: if you don’t mind where you are going, you ain’t lost.
If, on the other hand, you want to make a meaningful picture, your answer will have to be more specific.  You must be able to put into words why exactly you would photograph this plant. Otherwise, the best you can expect is what the famous Ansel Adams used to call “a sharp image of a fuzzy concept”.

The reasons for photographing a plant (or a part of a plant!) may cover an enormous range:
– because I like these flowers
– because I’m writing an article on this species
– because this is the first time I see the plant in the wild/ in this kind of environment/ in this area
– because I want to show the peculiar hairs on the leaves
– because I don’t have a picture of this species yet
– because the fruits remind me of …
– because I want to show the plant in its natural surroundings
– because normally the plant does not flower in this time of the year
– because I don’t know the name of the plant and hopefully the picture  can help me sort it       out
– because the fruits/buds/young leaves look so wonderful
– because I am awed by how this little plant survives in its hostile environment
– because I want to impress people with a picture of this rare plant in my collection
– because the picture will remind me of this wonderful trip
– because……, because……., because…….

Obviously you don’t have to restrict yourself to one reason. Do remember however, that each reason will demand a different approach. You will not be able to show a big  plant as  a whole and a detail of it, at the same time; if you want to show hairs or warts, you will probably need to use side lighting or backlighting, etc.
When you look at the list a bit closer, you will notice that part of the reasons have to do with the subject as such. In that case you will need a documentary, representative approach.  Other reasons have to do with your response to the subject, requiring an impressionistic,  creative approach.  Being aware of all this and responding in a suitable way, is an important step on the way to better pictures.

euphmult2009-06-06_DSC1976_lznres  euphmult2011_04_17#080_lzn-1res
Twice the same species (Euphorbia multiceps), but what a difference in pictures!

huerpill2011_11_25#014_lznres  huerpill_DSC4830_lznres
Huernia pillansii lends itself perfectly for making abstracts pictures

drosbico2011_09_13a#026_lznres  drosbico2011_09_13a#030_lznres
The first picture shows the plant (Drosanthemum bicolor) in its environment,  the second one tells us  much more about the flowers

mitrcliv2011_10_05 e.v.#231_lznres  mitrcliv2011_10_05 e.v.#233_lznres
The first picture shows the juvenile stage of Mitrophyllum clivorum, the second one gives an impression of an adult plant

A portrait of the bearded Crassula (C. barbata)

It would be hard to come up with a more apt name for this interesting little gem which is not just beautiful, but also interesting in an ecological sense.
The following pictures show how dramatically the appearance of the plants changes between late autumn and late spring. Please bear in mind that the plants occur in the southern hemisphere, and also that they only grow in the cooler and wetter months (autumn to early spring). They  are almost always found in shade, under shrubs or rocks.

Crassula barbata
Mid May (late autumn)

Late May

Early August

Late September

Early October

End of  October (late spring)
Now that summer is approaching, the rosettes have closed to minimize transpiration.  As a result of this, the cover of long hairs at the same time acts as insulation against strong light and desiccating winds.

Quality and direction of light in plant photography

As you probably know, photography means drawing (or writing) with light. Simply said: no light, no photography.  In this post I’ll describe two important  aspects of light:

Quality of light usually refers to its degree of diffusion, i.e. how  harsh or soft it is.
We tend to think that a clear sunny day is ideal for photography. As we will see, in reality it often gives the worst possible lighting, especially for taking plant  pictures.
A direct light source, such as the sun in a clear sky, produces harsh, contrasty light . The highlights and shadows are strong , resulting in big contrasts with abrupt transitions. This hard light also tends to make colours weaker.
Our eyes can cope with this kind of light much better than the camera, so that what looks acceptable in the viewfinder often turns out useless once it is photographed.
When the contrasts between light and dark are too big, many details will be lost, either in shadows or in washed-out areas. You may therefore have to use a diffuser to soften harsh sunlight and/or a reflector to get some light in a dark spot.
Hold the diffuser as close as possible to the subject. If you hold it further away, it will just throw a shadow on it.

clip_image002This picture was taken in harsh sunlight and is therefore very contrasty.
Even after spending quite a bit of time enhancing it in post-production, this was the best result I could get.

clip_image004This photo of the same species was made on a bright, overcast day, giving a much more pleasing result, even without any enhancing.
Using a diffuser on a sunny day would have yielded a similar result.


In this pair, the differences are rather more subtle. The first picture was made without doing any special; for the second one  I used a diffuser.
Although I like both of them, the first one reminds me more of the hot and sunny day on which it was made. Therefore it also gives a better idea of the conditions  these plants have to cope with. 

In many cases the sensible and careful use of flashlight may also help. If none of this works, you will have to decide what is more important to you: preventing the highlights from becoming burnt-out or the dark areas from turning completely black. The first option is usually best.
On bright overcast or misty days the light will be soft and diffused, with shadows evenly scattered around the subject. This kind of light produces soft contrasts and is easy to work with. It is very pleasing for photographing flowers. However, sometimes you may have too much of a good thing and end up with light that is too flat. In such a case, it is a good idea to add some shade to a small portion of the picture or alternatively to highlight another part so that it stands out more.
Reflected light is often soft too. Completely overcast days with heavy, dark clouds are not so good for flowers, but may work well for other parts of plants.

Direction of light refers to the camera position with regard to where the light comes from. There are three primary directions of light: front, side, and back. They all have their own characteristics and exert different influences on the mood of an image. Depending on your subject you should try different kinds of lighting to see what effects you like best.

When the light comes from behind you and falls directly on the front of your subject matter, we talk about front lighting. The entire subject is evenly lit and the shadows mostly fall behind the subject, so that this often appears lacking in volume and texture. In close-up photography this type of light also may cause problems by the lens or lens shade throwing a shadow on the subject.

Back lighting is the opposite: the light comes from behind your subject matter; it emphasises shadows and outlines shapes strongly.

clip_image006Back lighting can produce striking pictures, especially against a dark background

It creates strong contrasts and can produce a bright outline around the subject. Like side lighting it can make the colours of translucent objects sparkle. It is most effective with translucent or strongly coloured leaves or flowers. It may be necessary to underexpose 1-2 stops in order not to overexpose the bright areas; on the other hand it is sometimes advisable to open up 1-2 stops in order to allow detail in the subject. Therefore this is one of the situations where you should bracket your exposures.
Back lighting is not an easy light to work with, but it tends to create a strong mood and can produce images that are hard to ignore. Both side lighting and back lighting normally occur when the sun is low on the horizon (early in the morning or late in the afternoon). When you can photograph a plant from underneath, you may get the back lighting effect at other times of the day as well.

Side lighting is best for showing texture, as it gives the picture a 3-dimensional quality.
There is a clear separation between the light and the dark side of the picture. The shadows produced by side lighting may or may not be useful in composing your picture. Like back lighting it can make the colours of translucent objects sparkle.

clip_image008Because the light is coming from the side, we see not only the tiny dewdrops, but also their shadows on the leaf

External water storage in succulents

The great majority of succulents stores water in stems, leaves and/or roots. Some of them however, mainly members of the  vygie family (Aizoaceae) also make use of external storage. They  have an epidermis covered with extremely enlarged and swollen cells (so called bladder cells) that are able to store water. Amazingly up to over 50 % of the total amount of water stored by the leaves can be located in these cells.

The cells have another advantage too: they are so big, that they create windless spaces above the stomata (breathing pores) so that transpiration is reduced. When a plant start suffering from drought stress, the cells collapse. This obstructs the passage of air to the stomata, so that water loss is reduced even further

droscfbrev2010_09_09#189_lznres One of the best known examples is the genus Drosanthemum (“dew flower”)


Mesembryanthemum guerichianum

In this species (Mesembryanthemum guerichianum), the bladder cells are especially big on the calyx


Phyllobolus nitidus is named for its shining appearance (nitidus = glossy, polished or shining)