Photographing Primula in the Wild

Pam Photographing Primula agleniana in Tibet
One of the joys and pleasures of administering Primula World is seeing wild Primula images taken by others while travelling. Not every person is a world-class photographer or owns the best camera equipment, but that doesn't mean their images aren't exciting or useful. Even blurry images taken in poor lighting, can show variation and details of a Primula which can further our understanding of that species. I'm happy to see even one image, but it is always better to see many images of a species. See the Primula World image submission guidelines to see how you can be a part of Primula World. 

There are several key characteristics that when photographed can be helpful in identifying and documenting a species:

Flowers: Since the flower face is the prettiest part of the plant, it is the most photographed. Images can show useful details such as whether the flower is annulate or not, the position of the style, farina presence, hairs in the throat, petal shape and color patterns surrounding the eye. If the flowers are hanging, then don't forget to tilt the flower up to see the face! A thorough study would include splitting the flower open to see inside. It is rare that a single image of the flower face is enough to identify a species.

Flower faces (L to R): P. waltonii, P. bella, P. poisonii
Flowers are usually arranged in an inflorescence and the details of this arrangement and the length of the pedicels (which attach the flowers to the inflorescence) are important. The inflorescence is supported on a flower scape which varies in height and also in texture.
Classic spike inflorescence of P. vialii
with diagnostic red calyces.
Calyx, Tube & Bracts: It is just as important to photograph the back or side of the flower as it is to photograph the front. This shows the calyx, which is the outer most part of the flower (it protects the flower bud) and is composed of 5 sepals. How deeply the calyx is split into sepals and the shape and length of each sepal is very important to see. This view also reveals the floral tube which may vary in length and color. Bracts are modified leaves found at the base of the inflorescence that vary in shape and size.
Calyx, Tube & Bracts:
P. munroi (L), P. longipetiolata (R)
Leaves: It is no surprise that leaves are important in determining a species. They come in a variety of shapes and some species even produce more than one type of leaf during the year. Venation can be seen. Many species have farina on the leaves especially on the lower surface or hairs which may be photographed with extreme close-up lenses. The best leaf images are when a leaf is removed from the plant, with the petiole intact, and both sides are photographed, preferably with a scale.
Leaf studies: P. blini (L), P. advena (R)
Farina: Most Primula species produce farina, a powdery substance that may coat any part of the plant. Farina may be white, cream or yellow and may appear to be absent if washed off by rain.
Glandular hairs secreting farina
Seeds and Capsules: Though it is unlikely that anyone would be able to photograph Primula seeds while in the field, it is possible to do so later. Primula seeds by themselves can not determine a specific species, but it can point to a particular Primula Section.
Primula seeds
Seed capsules can also be used to determine an identification to the Section level. Of course we travel to see and photograph flowers! However, last years seeds capsules may still be present even if all the seeds have been dispersed or perhaps some new capsules are forming. A convenient image to make shows the flowering plant together with the old flower stalk and capsules.
Seed capsules: P. sikkimensis (L), P. calderiana (R)
Habitat and Location: A image of a wider view of the plant in habitat gives us ecological information plus relative plant size and population variation. Knowing the location of where the Primula was photographed in the wild helps me define distribution patterns. GPS coordinates can be determined in the field, or later estimated using Google Earth, but even general locations to the nearest place can help.
P. allionii habitat
Putting it all Together
I'm pleased to see any Primula images, but if you have time, a detailed study like that shown below of Primula boreiocalliantha is the pinnacle of excellence. Even common species need to be documented!

Field Checklist of images:
  
  1. Habitat – wide view showing the plants and their environment. Note aspect, moisture, base rock (granitic, limestone) and plant associations.
  2. Full plant – with measuring scale to show accurate height (or some indication of size, even if it is a finger or a hand.
  3. Leaf study – If permissible, remove a few leaves from several individuals by gently tugging downward from the stem so that the whole petiole remains with the leaf. Observe several plants and chose leaves showing variations. Image BOTH sides the leaves, side by side, with a scale. Take magnified images of any hairs, glands or pits on the leaf surfaces.
  4. Inflorescence study – Image the flowers from the back or side to show the calyx, bracts, tube, pedicels and upper scape. Note that pin and thrum forms may have different shaped tubes. Pull back a calyx lobe and document any farina inside.
  5. Flower study – Image the front of a pin flower and a thrum flower. If this characteristic is not obvious in the image, then cut a flower in half lengthwise and photograph it. If you suspect the species is homostylous, image several split flowers. If the flowers vary in color and size, and it is permissible, remove a few flowers and image them together with a scale to show relative variation. Tilt up flowers which hang down, to image the face of the flower.
  6. Farina – It can be hard to determine farina color from digital images due to color rendition problems and farina reflectivity. Observe and write down the farina color. Make sure your images show which parts have farina.
  7. Capsule study – If the plant is in seed or old seed capsules linger from previous years, image the seed capsule. Fresh capsules may be cut in half lengthwise to show the internal seed arrangement. Image the height of the scape with a measuring scale as the scape lengthens when the plant is in seed. If possible, show together the whole plant with old seed scape, and new flowering scape.
  8. Leaf rosette – Image the rosette (non-flowering plant is easiest) showing the new leaves unfurling in the center.
  9. Resting buds, bud scales - If the plant is imaged in early Spring, or late Fall, image the resting bud, documenting any farina present. If the plant is in flower, pull the leaves back to show any bud scales or a sheathing base.
  10. Root/stolon study – If permissible, remove a plant from the ground, and image the colors and structure of the roots. Image any stolons.
  11. Fragrance – note the fragrance of the flowers and/or roots and write it down.
* Notes can be written on paper in the field and photographed with the plant. Similarly the display of a GPS can be photographed with a plant if the camera is not GPS enabled.

 
Remember: Take as many Primula images as you can....and then take one more!

Pam Eveleigh © 2017

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