Reports of the 2017 Talks
Geology and flora from west of Death Valley to the Sierra NevadaCalifornia
11th January 2017
Chairman’s Evening: Sue Miles and Ian Sutton
The talk covered a road trip from an altitude of 282 feet below sea level to around 10000 feet. Traveling from Death Valley via the Owen’s Valley to Yosemite National Park in the Sierra Nevada, visiting Whitney Portal, Mammoth and Mono Lake on the way. This is Basin and Range country. The basins being north - south valleys separated by ranges with steep eastern slopes. Death Valley and the Owen’s Valley being the best known and most westerly basins and the Sierra Nevada being the highest and most westerly mountains separating, moist western California from the dry Basin and Range.
The rocks are almost all granites formed from continental rocks by the now defunct Farrallon plate subducting from the west under the area. These being subsequently uplifted by the later plate movements that also formed the basin and range and uplifted the Sierra Nevada. These movements continue and have also resulted in volcanic activity, most recently the very large Long Valley eruption of about 70,000 years ago.
There are calcium carbonate towers at Mono Lake formed under water by hot springs and now exposed by a drop-in lake level due the diversion of its water source.
In the lower and arid areas the soils were granite gravel, whilst at high altitude plants utilised cracks in the granite or small wet basins and meadows. Plants were shown growing in all of these habitats Plants from wetter areas included species plants from which well-loved garden plants such as Penstemon, Iris and Mimulus have been developed. Other plants shown included several species of each of Aquilegia, Delphinium, Gentiana, Castilleja, Dodecatheon and Lupinus.
The current and retiring Chairmen were thanked by Robert Rolfe.
Yosemite National Park
8th February 2017
Western Crete Vic Aspland
A welcome return by Vic Aspland saw him take us on a journey from sea level to an altitude of 4500 feet looking at the plants and scenery on the way.
Vic and Jan have visited Crete at least 18 times in both spring and autumn. The best dates for the flora are the second half of April and the second half of October.
Beach and low level plants included Glaucium flavum and Cakile maritima.
Amongst the geophytes we saw three species of cyclamen, four of tulips, Fritillaria messanensis , Colchicum creticum, Sternbergia lutea (or sicula)
Cliff plants included some campanulas including the endemic Petromarula pinnata and the highest clinging to a limestone cliff at 4500 feet was Aubretia deltoidea.
About 30 million years ago the Aegean continent emerged from the beneath the sea and was colonised by plants from what is now northern Greece and Turkey. It then started to sink beneath the waves again to form islands The eastern islands remained attached the Turkey until during the last one million years and thus share its flora. A peninsular formed in the west comprising the Peloponnese, the Cyclades and Crete having a distinct flora. Crete separated and became an island 8 million years ago and is thus the oldest Aegean island with the largest number of endemic plants.
8th March 2017
Why not make a miniature garden? John Dower
Most members were familiar with John Dower’s miniature gardens, having admired them at the Loughborough Show, so it was nice to meet and hear the man himself.
John felt that the best results were obtained with round, shallow pots, half full of drainage and built up to higher than the pot itself to make a landscape. As many as 40 plants can be crammed into a handlable pot.
Any free draining compost can be used with no feed. Pots can be planted or partly replanted right up to just before a show so long as the result looks established. John showed a video of him doing this with a desert spoon used as a spade. Rocks of various types, although not mixed, can be used to give height and an attempt should be made to tuck plants roots under the rocks. Although any rock can be used, tufa is often the best as plant roots can penetrate it. Many images of John’s gardens were shown plus many of other peoples. John was amused by some people’s attempts to populate their landscapes with miniature buildings and characters. Members agreed, NO GNOMES!
13th September 2017
Steve Furness Sempervivums and some Saxifragas
Dr Furness is an academic, scientist and the owner of the Alpine Plant Centre at Calver.
He said he was only going to show us pretty pictures but fortunately the botanical science still showed through.
Although there are superficial similarities between Jovibarbas and Sempervivums , Jovibarbas are an ancient genera that do not hybridise whereas sempervivums are much more modern. Both are Old world plants. There are thousands of selected forms (varieties) in an amazing range of colours that were illustrated with high definition images. The plants are highly stress resistant and thrive growing on bare rocks or roof tiles where they were considered protective by the ancient Greeks.
Saxifraga are also Old World plants and many also thrive in dry, nutrient poor situations and it was these that were briefly illustrated.
11th October 2017
Rick Lambert Glaciers and the flowers around them
Rick demonstrated that the special habitat around glaciers is very important for special alpine plants. There are glaciers on every continent for the equator to the poles and images of several splendid examples from around the world were shown. The erosive power of glaciers also provided nutrients into river systems and the sea.
Most of the plants shown were from the Grossglockner in Austria and Sans Fee in Switzerland that Rick had explored extensively. Saxifrages featured strongly but also eritrichium, gentian, primula, soldanella.
An interesting talk giving clues from the natural environment on why some of the above genera are so difficult in cultivation at low altitude.