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Just To Get Out Of The Rain
Saxifraga berica, Saxifraga arachnoidea and
Saxifraga petraea and other saxifrages of Northern Italy
by Paul Kennett
At a Saxifrage Society meeting at Wisley last year, I mentioned to Adrian Young that I
would be exploring the Lake Garda area in Northern Italy that summer. When I added that I
particularly wanted to see Saxifraga arachnoidea, he asked "Why?" in a
way that indicated that he doubted my sanity. I had to admit I didn't really know why. By
most accounts it seemed a scrawny thing and the Garda mountains certainly have more
conventional delights such as Daphne petraea, Physoplexis comosa, Silene elisabethae,
and of course, Saxifraga tombeanensis.
In the weeks that led up to my visit, though, it was S. arachnoidea that
continued to dog my thoughts. There were three principal contributory factors. Firstly, a
full-page photo of it in Herbert Reisigl's Blumenwelt der Alpen that makes it look
the equal of any of the most sumptuous European alpines. Admittedly the specimen looks to
me as if it has been subtly "massaged" into a tighter clump than would be
natural, and the colour values of many of the photos in the book seem enhanced.
Nevertheless, it was sufficiently impressive to elevate the species to my desiderata.
Secondly, in The English Rock Garden, Reginald Farrer rather surprisingly chose
to eulogise it in the peculiarly rococo style of prose poetry that he normally reserved
for his most cherished flowers:
In the damp silty grottoes under the Daphne's cliff on the Cima
Tombea this very rare species may be seen, making masses so filmy and evanescent that you
expect them to be blown away on a breath like the yellow-starred films of cobweb that they
seem. It is as frail in root and stem as the hope of a lost cause, then spreads into a lax
flopping jungle of weak fine branches set with broadly oval and minute toothed leaves as
flimsy and frail as a lovers' vows; and the whole mass is interwoven with a long soft
twining fluff of shaggy silver that gives it the frosted and dew-dropped iridescence of a
dream. The little stars of blossom spring here and there on fine stems at the ends of the
branches, and are of a pale diaphanous yellow in keeping with the ghostly unreality of the
whole apparition.
Lastly, it was apparent from the literature that the species was rare, localised, and
elusive even in its known haunts. I had spent 4 days in the region before, not in active
pursuit of S. arachnoidea, but checking every likely looking niche I encountered
without so much as a sniff. I decided it was clearly a plant a self-respecting plant fiend
such as I had to find.
The main expeditionary party consisted of my wife, my one-year-old son, and myself.
After the first few days we were joined by my in-laws, who had a very important role to
play by freeing me from parental duties often and long enough to satisfy my botanical
urges.
Lake Garda is the largest Italian lake and lies at the southern edge of the Alps. It
was formed where a giant glacier formerly debouched onto the Po plain. Its altitude is
only 65m above sea level, and the climate and immediate flora is Mediterranean. However,
limestone mountains to the east and west tightly embrace it, and these plunge dramatically
into the water, particularly along the western shore. On the east lies the Monte Baldo
range, a narrow ridge with easy access from roads and cable cars. To the west lie a jumble
of hills and jagged peaks with more difficult access. These are collectively known as the
Tombea range, and form with the ranges immediately to the north and west, the Giudicarian
Alps.
Neither range is of any notable height, the highest summit being just 2218m, but they
possess a rich alpine flora with a number of interesting endemics. Supposedly this is
because, being glacier free, they became a refuge for plant species during the ice ages.
We had flown to Verona, and then were whisked by coach to our hotel in Limone sul Garda
on the north-west shore of the lake. Limone is a hotel resort town, popular with Germans,
with many hotels and restaurants, and a steamer service across the lake to the foot of
Monte Baldo. We found it to be an excellent base for exploring the area. The road beside
the west side of the lake is not for the faint-hearted; there are innumerable tunnels,
tight corners and a preponderance of oncoming coaches. We had hired a car; this is not
cheap, but necessary as a time saver to get to remoter places. It is also considerably
less fraught than public transport where you don't speak the language.
Limone is famous for its ruined lemon groves, and these must be a unique example of an
economy based upon a pun. The place name is derived from the Latin for a border; this was
an old frontier town, and it still marks the boundary between two Italian provinces.
However, Limone is also the Italian word for lemon, and, apparently for this reason only,
someone 300 years ago thought it would be a good idea to grow lemons here. The climate
here is very marginal for this crop, and elaborate walls were built in an only partially
successful effort to protect the blossoms from the cold mountain winds. The transport
costs to market were expensive too, but until fairly recently there was still apparently a
premium to be had for lemons from Limone.
We had chosen the two weeks from 21st June to 4th July, thus coinciding with Wimbledon
fortnight. This, we supposed, would attract all the rain in Europe with Centre Court being
its epicentre. We were wrong. The first week was a succession of promising mornings,
leading quickly to cloud and the onset of steady rain.
On the Wednesday we explored the road described as "rather adventurous" in
Webb & Gornall along which S. arachnoidea had been seen in three places in
1985. This road is a narrow, unmetalled track with deep craters, boulders and wash-outs
running through a superb limestone wilderness, from the villages that make up the
community of Tremosine almost vertically above Limone, up to the Tremalzo pass. It is
negotiable in a ordinary car, although you will be in first gear for the most part, and
suffer the ignominy of being overtaken by mountain bikes. Furthermore, if your driver is
botanically minded, as ours was, their loyalties will be dangerously divided between
watching the road surface, and scouring the rocks for plants. One thing is certain; you
won't see many other cars!
Suffice it to say that we didn't find S. arachnoidea either. We were
particularly convinced by one particular overhanging cliff, dripping wet in places, that
we passed underneath as the road curved around a range called Pozza del Lupo. This had
curtains of Physoplexis comosa in flower, and the stickily hairy Aquilegia
thalictrifolia. We had time enough to pay respects to a colony of Daphne petraea
we had seen on our last visit near the Tremalzo Pass before the rain drove us, soaked and
chilled from the mountain.
That evening, it was evident that the less botanically inclined party members desired
to visit a city, and, for a change, not drive around in the rain all day staring at rocks.
Luckily I had a plan. I had photocopied all the pages from Webb & Gornall that could
conceivably be relevant to this trip. Among the pages I had included was the entry for Saxifraga
berica, although at the time I felt it unlikely to be used. Suddenly, though, it had
sprung to the top of my list because a) it grew near a city, Vicenza, and b) this was down
in the Po valley, where the weather ought to be less hostile. I suggested that we should
visit this historic town, and while we were there, knock off this rare Saxifrage too.
S. berica is a very rare species indeed. It is endemic to a small part of a
small range of hills, the Colli Berici. These hills rise 10km south of Vicenza to just
450m, and represent the last hurrah of the Alps before the unalleviated flatness of the Po
basin. Even here it is restricted to a rare niche, overhanging shady rocks. The next day,
the plan was simple, go to the hills, find the overhang, find S. berica, then have
lunch and an afternoon in Vicenza.
We left Limone in a downpour, with the rivers bringing down whole trees that joined
rafts of detritus out in the lake. By the time we reached Costozza, the little town
beneath the north east end of the Colli Berici, the sun was out, and indeed, it was
obvious that here we were in the Mediterranean climate proper. From the town, there are
signposts to the scenic track that mounts the hills, exaggeratedly referring to them as monti
rather than colli. This track skirts the gaping limestone quarry that spoils the
town's view, and ascends in a series of gentle hairpins past imposing villas set amidst
tracts of scrubby woodland.
We stopped, and I spent an hour and a half looking for likely overhangs, but found only
impenetrable Cotinus and Paliurus scrub, a Scarce Swallowtail butterfly and
dry rocky slopes alive with snakes. As a final attempt, my wife suggest I try a track she
had spotted that diverged at a tangent from one of the hairpins about halfway up. This
track soon doubled back to a house, but a footpath lead on further. Now the vegetation
suddenly took on the aspect of a submontane wood; there were Hepaticas, Helleborus
niger and ferns underfoot. Then rocks appeared on my left, and a little further a
small cliff loomed amongst the laurel trees, no more than 20 feet high and 20 yards long.
As I picked my way through brambles to its base, I could see what could only be S.
berica here and there along the entire length of the rock.
Looking closer, I could see that my visit could have been better timed; at the end of
June, the colony's flowering season had all but finished. There were a few flowers
remaining, but the plants themselves were now straggly, and their glandular hairs had
caused the tufts to become matted upon themselves. Interestingly, some of the larger
specimens were already showing fresh growth in their centre, thus confirming the perennial
nature of the species; I somehow expected them to be summer dormant. The overall effect
was admittedly not very photogenic, but I imagined that S. berica would put on
quite a pretty show of white stars for a visitor in April. One last point I noted was that
it grew only on the lower half of the cliff, where there was shelter from the evergreen
shrubs, and a sizeable overhang. Even here it picked out only round eroded cavities that
appeared slightly moist.
This is not the place for a full description of S. berica; I refer you to Webb
& Gornall's book, but the most curious feature is its unequal petals, which it shares
only with its closest ally and the non-European section, Irregulares. Unlike the Irregulares,
S. berica's petals all differ in size; the largest can be twice the size of the
smallest within the same flower.
S. berica's closest relation is S. petraea, a biennial with more deeply
lobed leaves and slightly larger flowers. This ranges across the south-east fringe of the
Alps from Monte Tombea across to the karst region of Slovenia and Croatia. Its nearest
site to the Colli Berici is 60km away on Monte Baldo, and it is not hard to imagine S.
berica representing an isolated population that found itself cut off climatically in
this interglacial period, and which has adapted by evolutionary means to local conditions.
I did collect a small pinch of the abundant seed, about three capsules full, from S.
berica. I passed half on to someone else in the Saxifrage Society, and sowed the rest
directly into crevices on a tufa boulder, as a kind of homage to its habitat. I have
planted this boulder vertically in gritty compost in a large pot, and kept it in a cool
greenhouse, watered from below only. The seeds germinated rapidly; one plant has made
rapid progress, and as I write 8 months later, it is opening its first flower. There are
about 20 more, much smaller ones on the tufa plus a few evidently blown from their
crevices that have germinated in the grit. Those that are on drier, sunnier aspects show
signs of stress by a bronze tinge to the leaves, but all now seem to be responding
positively to the onset of spring.
S. berica, S. petraea and S. arachnoidea form three-quarters of series Arachnoideae
within section Saxifraga, according to Gornall's classification system. Previously,
under Engler's system, S. berica and S. petraea were in the Tridactylites
section, while S. arachnoidea was a member of the Nephrophyllum group. The
fourth member of the series, S. paradoxa, from Styria, was usually placed in the Tridactylites
also, but had at one time been granted a genus of its own, Zahlbrucknera.
The 4 species are all endemic to the South Eastern Alps and its environs, and all share
the unusual habitat of shady overhanging cliffs, rocks and cave entrances. This niche is
not restricted to this group amongst Saxifrages; I have seen S. hederacea and S.
chrysosplenifolia in a similar habitat around the entrance to Tzanis cave on the
Omalos plateau in Crete. After finding S. berica, my target had now altered from
just finding S. arachnoidea alone, to acquainting myself thoroughly with the Arachnoideae.
During the fortnight, we made two assaults on the Monte Baldo massif. We skirted the
lake around to Malcesine, and then rode the cable car to the summit ridge. From here, the
view is stunning; Garda, 5000 feet below, appears to be directly down beneath your walking
boots. The Tombea range across the lake becomes just an undulating plateau, and your eyes
are drawn away to the eternal snows of the Adamello range in the distance to the
north-west. The view this particular day was, however, short-lived because, in no more
than half an hour, the sky had darkened to a leaden hue. Across the cloud base peculiar
furrows and striations developed, as the coming storm was whipped up and over the spine of
Baldo by the east wind. Lightning ranged nearer and nearer, and we were forced back,
half-running, to the sanctuary of the refuge, and retreated back down the mountain before
the cable car was shut for safety.
On the first rocky slopes encountered going south, however, I had noted abundant leaves
of the Baldo endemic, Callianthemum kerneranum already over, growing with strong
colonies of Saxifraga mutata, frustratingly not yet in flower. This was my first
ever wild encounter with this weird Ligulatae species whose squinny orange petals
it borrows from S. aizoides.
On another day we optimistically packed a picnic, and explored the old military road
that runs north-south behind almost the entire length of the ridge along the 1430m
contour. On this range in 1911, Farrer collected a plant that is still widely grown by
alpine enthusiasts, S. paniculata 'Baldensis'. I had always assumed this was simply
the local form from this mountain. S. paniculata does grow in vast abundance on the
limestone rocks all along this road, but nowhere did I see any plant that even remotely
approximated Farrer's collection, or was anything other than typical. According to its
finder Saxifraga paniculata 'Baldensis' grew on the highest summit ridge and so
probably represents an extreme microform adapted to the extra exposure.
Where the road passes below Cima Valdritta, the highest point of the chain I noted an
unusual form of S. aizoides, dwarfed and growing as a limestone crevice plant, and
with orange flowers. The star plant at this point though was undoubtedly Paeonia
officinalis. We had seen the leaves in several places around the mountain, but here I
could at last scramble the 10 feet up the roadside rocks, gaze into its rosy chalices, and
drink their sweet scent.
On the road down, we passed beside a small reservoir at about 1000m by the village of
San Valentino. Just below the dam, in a gorge, my wife suddenly told me to stop because
she had spotted a flower she didn't recognize on the wet rocks. A swift piece of reversing
proved itself worthwhile when the mystery plant was recognized as S. berica's
biennial sister, S. petraea. Here there was a small colony of some 25 individuals
in full flower scattered beneath an overhang around a culvert. According to Webb &
Gornall, as well as Winton Harding, this can be a very worthwhile plant in cultivation,
but Farrer rather unnecessarily noted it was rare in nature, but even rarer in gardens,
and deservedly so. With its softly hairy leaves recalling a jagged Dovesfoot
Cranesbill and slightly unequal notched petals of pure white, I deemed it dainty and
wholly charming.
With the available days fast dwindling it now became imperative once and for all to
locate S. arachnoidea. This would demand a full day's botanical exploration in its
heartland, the Tombea range. My in-laws are game for most things; I once persuaded them on
the first day in the mountains to climb 4000 feet to see S. florulenta in the
Maritime Alps, by selling to them the concept of The Ancient King as being the plant
equivalent of the Giant Panda. The Cobweb Saxifrage was no Giant Panda though; its
notorious elusiveness and the modest reward its discovery confers suggested a kinship with
the quarry of The Hunting of the Snark. In the end, a day spent with their grandson on the
steamer to Malcesine proved a greater attraction, and I was left to my own devices for a
day.
Some references deny that there is any such mountain as Monte Tombea. This is not
entirely factual. The highest point in the Tombea range is Monte Caplone at 1976m, set in
its dead centre. This is the highest summit of an east-west ridge shown on old maps as
Monte Tombea; current maps name a subsidiary top Cime Tombea. On its southern flank the
headwaters of the Fiume Toscolano gather, and this drains the Val Vestino, the largest
upland valley between the lakes Garda and Idro. Webb & Gornall state that the upper
part of the Val Vestino is the region in which S. arachnoidea is commonest, so this
was to be my target.
The drive there from Limone is a scenic one taking an hour and a half at best. I headed
down the lake to Gargnano where a side road snakes steeply up the wall of the Garda basin
and emerges in the valley above. I followed the valley bottom road past the large
reservoir that now occupies its middle section, and signs were taken towards Magasa, a
hilltop village where the roads stop.
On the approach to Magasa the route hairpins across a tributary valley, and passes
beneath an overhanging cliff festooned with Physoplexis comosa. A perfect S.
arachnoidea niche, I thought; for such a local plant S. arachnoidea has a large
altitudinal range, colonies being known from near the summits right down to 600m. The dry
silty underhangs in this case, though, proved to be exclusively occupied by Silene
saxifraga and Moehringia bavarica var. insubrica. This latter is a
sandwort with glaucous leaves and belongs to a genus that, like the Series Arachnoideae,
has a number of local species in the southern Alps that specialise in this unusual
habitat.
Just before Magasa a side road with hairpins so tight they required 3-point-turns,
heads up to a community called Denai, and here I parked with Monte Tombea before me like a
sleeping giant. I walked passed fields infested with Hellebores towards the mountain, then
followed path 67 eastwards through dense forestry. On and near rocks in this wood I again
found S. petraea, this time a stronger colony with outliers 300m away. Most plants
were in overhung rock crevices, but others had thrived in deep detritus amongst other
vegetation, under the shadows of the trees. Still others grew on small boulders in an
adjacent field, with only a vestige of overhead protection. This species was clearly not
as fastidious in its choice of habitat as the others of its section.
My route then almost doubled back onto path 66, which heads 600m up to the Tombea
ridge. This is an excellent walk. It first leads under a large bluff again adorned by Physoplexis
comosa, but this time accompanied by large mats of Daphne petraea, which for
the most part, appeared not to have flowered. Half way up a stream is crossed, on whose
banks grow the unusual Leuzea rhaponticoides, resembling a giant Knapweed. The
woods give way to turf with Primula spectabilis, now finished, and Viola dubyana
where the soil had been disturbed.
Just as things were getting interesting, the clouds descended, rain and hail began, and
thunder was heard. I made for the gorge of the stream, declared myself an early lunch, and
took shelter, like S. arachnoidea itself, beneath a rocky overhang. An hour later I
had had time to consider why S. arachnoidea had adopted such a peculiar habitat.
Any evolutionist would no doubt find this question itself wrong-headed: S. arachnoidea
didn't adopt the habitat, it is nearer the truth to think of species as
"children" of their environment. They are created and moulded into winning
designs over generations by the selection pressures of the ecological niches themselves.
However, as I sat there huddled against the wind and rain so intense that the meadow herbs
appeared to be both waving and drowning, it occurred to me that the title I have given
this article was possibly a more satisfactory answer.
For once, the rain eventually relented, and I continued my climb, shortly reaching a
T-junction of paths. This is the Sentiere Antonioli, an old military road, now overgrown,
that follows a contour below the Tombea ridge, and then continues over hill and valley to
the Tremalzo pass. I headed east along it, a path marked number 69, towards the Bocca di
Campei, the col between Cima Tombea and Monte Caplone. A hundred yards or so along this
path my eye was caught by a colony of the common Saxifraga caesia, and what
appeared to be a giant flowered form in its midst. An instant later I realised that I was
looking at S. tombeanensis, albeit a small specimen with only 3 flowers.
This classic Kabschia species with green spiny leaves and small cymes of pure white is
of restricted distribution, but extends beyond the range for which it was named north into
the Brenta Group. Another Kabschia, S. vandellii, is also known from the Tombea
massif, but I did not see this. I worshipped my find briefly, then sought a better
specimen. This search proved initially fruitless apart from finding a solitary plant of Silene
elisabethae, another one of the superior endemics of the region, with its giant
ragged-robins sitting atop glossy, sticky leaves, and Saxifraga mutata, as before
not yet quite in bloom.
The path sweeps around north at this point, and heads towards an archway blasted
through the rocks. Before reaching this, however, I passed a slab of limestone on my left.
I could see it overhung its hidden base, so I clambered up to it. As my eyes came level
with its foot, I finally came face to face with S. arachnoidea. Set back four feet
under the ledge were about 8 plants in their prime, growing in pure lime dust eroded from
the slab, and sharing this specific habitat with no other species. In less shady parts of
the overhang though were the Silene saxifraga and Moehringia bavarica var. insubrica
I had seen earlier down below in the valley.
S. arachnoidea's pretensions to the higher echelons of alpine society were
reinforced by the aristocratic nature of its other closest companions: within 5 feet grew
both Physoplexis comosa and Daphne petraea, and the rosy flowers of the
latter could be seen 20 feet straight up. And, 8 feet above, a rocky protuberance was the
throne for a huge S. tombeanensis fully 2 feet across, covered with developing
fruits. For me, though, as you will have guessed by now, there was only one monarch here,
and I prostrated myself before the Cobweb Saxifrage, and took enough photographs to
satisfy a member of the paparazzi. Then I examined with wonder the minute details of the
bizarre leaves wrapped in cotton-wool through my hand lens.
The world distribution of S. arachnoidea is tiny; all the colonies are within
18km of the nearby village of Storo. I have demonstrated to my own satisfaction too, that
it is not at all common within this area. There is a suggestion in the literature that the
colonies are dynamic, and are not to be found in the same places for long. If true, this
is surprising; its habitats are fairly static and stable, and free of competition. It is
also hard to imagine a mechanism for conveying seed from one suitable ledge across
kilometres of unsuitable land to another ledge with any degree of efficiency. Perhaps
instead, seed reservoirs are present in the substrate in the known sites, and only
germinate in years when the microclimate suits. The individual plants are perennial but
short-lived, so colonies would seem to die out and appear elsewhere.
One detail I noted differs from Webb & Gornall's description; they state the flower
colour is off-white whereas other sources say yellow. To my eyes, and judging by my
pictures, they were clearly yellowish tending if anything towards green.
I would have to confess that I was disappointed with the quality of my photos of the Arachnoideae.
I had expected to be taking pictures of alpines in the sunny south Alps, and ended up
photographing plants from extremely shady habitats in the rain. I routinely use 100 ASA
film for its finer grain, but in these circumstances it is just too slow. Anyone following
in my footsteps is advised to take a second camera body, if possible, loaded with 400 ASA
film. I certainly intend to do so when I eventually visit the Koralpe range in Austria,
for visit it I must in order to find Saxifraga paradoxa, the remaining and dingiest
Arachnoid Saxifrage. Perhaps, Adrian, you were right after all to doubt my sanity!
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