Saturday, 26 January 2019

New Zealand Veronica: how high do they grow?

At the moment, New Zealand’s largest flowering plant genus is Veronica (the speedwells and hebes), with 122 native and 19 introduced species (maybe 124 and 17, since we’re not sure about the biostatus of two). But pretty soon, new discoveries in Carex might knock Veronica off the top spot.
One interesting thing about native New Zealand Veronica is that—apart from the Australian V. calycina and V. plebeia that some botanists regard as natives—they’re all derived from a single ancestor that arrived here about 10 million years ago. That means their huge range of growth forms, leaf shapes, flower shapes, and capsule structures and functions have evolved here in New Zealand, likely as adaptive responses to a range of soils, climates, pollinators, and means of dispersal.
Last week, I’ve been collecting data on elevational ranges for all New Zealand species of Veronica, to add to the Flora of New Zealand text I’ve been preparing. Fortunately, the main herbaria (pressed plant collections) have digitised their Veronica labels, so I haven’t needed to look again at all the specimens (I’d already identified them).
The first thing that struck me is that only about half the specimens had a recorded elevation on the label. That’s not so surprising though; a lot of the collections are old, and it wasn’t always easy before good maps and GPS to estimate an elevation. Should I go through these and infer an elevation? I decided not to, for two reasons. First, there are already a lot of collections that do have good data, and my assumption is that those will give me a pretty accurate range for each species. Secondly, the locality data on these old specimens is often vague, and inferring their elevation might introduce errors.
Flowers of Veronica melanocaulon, from Mason River, N. Canterbury.

Indeed, I found a good example that shows the need for caution. A fairly old collection of V. melanocaulon was simply labeled “Mt Terako”. But somebody later had helpfully tried to add value by inferring an elevation for it, looking up Mt Terako on the map to give a databased figure of 1740m. When I compiled the data to get overall ranges, this was the highest elevation for V. melanocaulon by about 800 hundred metres. V. melanocaulon plants are found along river and stream banks, not on mountain tops, and while I have no doubt it was collected in the general area of Mt Terako, I’m also sure it wasn’t at 1740m.
Veronica elliptica, at Milford Sound.
About 30 species can be found at or near sea level, but only a few—like V. elliptica at 0–45 m—are strictly coastal. Many, like V. odora, have larger elevation and habitat ranges that only sometimes come as low as sea level. V. lilliputiana plants grow on silty or muddy shores of lakes and ponds and only sometimes find suitable sites near the sea, for example in lagoons at Lake Forsyth and Otago Peninsula.
Veronica lilliputiana (scale = 1 mm).
At the other end of the spread, Veronica achieves some of the highest elevations for flowering plants in New Zealand. At the very top is V. birleyi. Its lowest record is 1830 m, and it has been collected as high up as 2835 m. I’ve only seen it once, at Copland Pass near Mt Cook, and then only because a couple of climber friends took me there safely. I once thought I’d found V. birleyi at 1470 m on the Takitimu Range in Southland, but closer examination showed those plants were a new species, V. spectabilis, that’s most likely its nearest relative.
Veronica birleyi (left) has smaller flowers (not shown) than the similar V. spectabilis.
Veronica epacridea is a close second, reaching an elevation of 2745 m, but it has a larger range, down to 638 m. The high altitude veronicas are mostly members of the snow hebe and connatae informal groups. Nine species or subspecies are not known at or below 1200 m, roughly the old 4000 foot mark, and eight (not always the same ones) reach maximum elevations of 2000 m or more.
Veronica epacridea on the Torlesse Range, Canterbury.
What’s in between? The bulk of the genus is neither coastal, nor high alpine. How many are subalpine to alpine versus lowland to montane? We could use the natural tree-line as a convenient dividing point, except that it varies, from 1500 m in central North Island, to 900 m in Southland (Alan Mark’s “Above the treeline” has a good introduction to the alpine zone and its environments). I can’t be bothered going through my list one by one to assign them carefully to “above” or “below” tree-line groups, otherwise I’d probably be writing this as a scientific paper, not a blog post.
About 65 species and subspecies have a minimum elevation above 600 m and a maximum over 1500 m, so they’re mostly found in the zones above tree-line. And about thirty native species and subspecies have maxima that are below 900 m, so they’re lowland to montane. Another thirty or so have maxima clearly above, and minima clearly below tree-line; they seem to be plants of the montane to subalpine zones.
Veronica epacridea has the biggest overall range, at 2107 m. That’s because, although it’s mostly an alpine to high-alpine plant, it can be found occasionally on screes and cliffs at much lower levels, perhaps establishing sporadically from seeds or even bits of plant that have blown down from above. V. lanceolata also has a wide range (1708 m). It has narrow-leaved forms found at low altitudes in coastal Taranaki and Coromandel and forms with broad fleshy leaves in the North Island mountains. Its local populations are maybe adapting to different conditions and could be in the process of diverging into separate species.

Thursday, 28 December 2017

What I did last year for hay fever.

Disclaimer: the following is not medical advice. It's just a description of what I started doing for my hay fever last summer. And it's not research based: there's no control and the sample size is n = 1.

I guess botanists suffer from hay fever at about the same rate as any other profession, but being allergic to your job is always good for a laugh, at least for other people. I suffer pretty badly from hay fever, mostly in November, December, and the first half of January. Allergy skin testing shows I'm very strongly allergic to cocksfoot (Dactylis glomerata), quite strongly to some other grasses like timothy and ryegrass, and mildly to plantain and some tree pollens.
Cocksfoot produces masses of pollen from those large pink anthers.

Over the years, medications have improved. The first I used (mid 1960s) were Polaramine 2 mg, little pink pills that were very effective, but they made me drowsy. I've tried lots of others as they came onto the market and most have been pretty good. But for the last ten years or so, after some nasty side-effects, I've avoided pills altogether and instead used a combination of nasal spray and eye drops to topically treat the symptoms. That's been very effective. However, about five years ago pharmacists started warning me against continuous use of the eye drops. Apparently continued use of anti-histamines can worsen symptoms of prostate enlargement in men with benign prostate hyperplasia (i.e., many men my age). I've also tried the desensitisation injections, but it was tedious and only lasted a few years.

So last year I had a bit of a think. I realised that my main allergen, cocksfoot, starts flowering several weeks before I get my first hay fever symptoms. It seems a bit of pollen in the air isn't enough to set my hay fever off. It's only when levels get really high—peak flowering—that I succumb to that debilitating itching and sneezing and sometimes even to skin rashes. Also it also doesn't start as soon as I go outside; it usually takes at least 15-30 minutes, often a lot more, to kick in. And it's worse at certain times of the day.

I assume that pollen settles in the film of tears on my eyes, and blinking concentrates it along my eyelids; once enough has built up there, it starts to generate a noticeable allergic response. So, I wondered, what if I could simply wash it away? How quickly would it accumulate again? I bought a bottle of a proprietary eye wash, mostly just to get the little plastic eye-wash cup that came with it.

Washing my eyes a couple of times a day seems to be enough to prevent them from itching, except when I'm outside during peak cocksfoot flowering; then it can be necessary every 30–60 minutes. It doesn't even have to be the commercial eye wash, just clean water works fine too. With hindsight, I remembered I don't get hay fever for a while after swimming.

After a bit of experimenting, I found that opening my eyes under the stream of water in the shower does the job pretty well and lasts all day for much of the hay fever season. I cup my hands under each eye and fill the space with water, then blink and roll my eyes up and down and right and left a few times. Lately I've been comfortable just opening my eyes under the stream of water (I turn the temperature down a little).

I spend most of my time in the Wellington city and suburbs, where there is a lot less flowering grass than in the countryside. When I'm outside doing field work, I carry a small bottle of tap water, an eye wash cup, and a small towel, so I can stop and rinse my eyes whenever I need to. It's no more uncomfortable than opening your eyes when swimming underwater.

Itchy eyes are my main hay fever symptom, but I can also get a runny nose. I found I could learn to tolerate rinsing my nasal passages in the shower too, and that gives good relief. But mostly just washing my eyes seems also to prevent the worst of the runny nose and sneezing.

Rarely, if I'm out on a sunny hot day, I can have a pretty extreme rash and even swelling, wherever my skin comes into contact with pollen. That's a photosensitive dermatitis, caused by a combination of pollen, sweat, and sunlight. To protect my skin, I just wear long trousers and long-sleeved shirts.

Last summer, and again this year, I used this regime and I didn't need any drugs at all. I had a bit of hay fever, but nothing too uncomfortable. As long as I had some water and my eye wash cup with me, I found I could very quickly put an end to itchy eyes (the itchiness disappeared almost instantly after washing). My hope is I'll never need hay fever drugs again.

I repeat: this is not medical advice. It might not work for you. There might be risks I haven't thought of. But I thought I had nothing to lose in giving it a try. It's probably safest to use distilled water or clean saline solution; a proprietary eye wash would be even better. If you use warm shower or tap water, you'd want to be sure the hot has been heated sufficiently to sterilise it (otherwise legionnaire's disease might be a risk).

If you do try it, it's at your own risk, but please post a comment and let me and others know if it helps, or not. I'd also welcome comments from medical professionals, because I might be overlooking something important. I did discuss it briefly with my doctor; he looked skeptical and slightly disapproving, but didn't give any particular advice.

Tuesday, 15 March 2016

A dry summer in Wellington.

I haven't blogged here for a couple of years. I've been busy doing other things, mostly with a camera, and I'll have more to say about that in good time.

It's been a warm and dry summer in Wellington. Until Christmas it was cool, even cold, but since the beginning of January it's been much warmer than usual and very dry. Warmer than usual in Wellington isn't what most people would call warm, but daytime temperatures have stayed in the mid-20s for weeks and some nights have been uncomfortably warm. We had a shower of rain, briefly, about three weeks ago, and the last one before that was probably two weeks prior. That's pretty unusual round here, and our plants aren't used to it.
Pate, Schefflera digitata. The leaves aren't really wilting, but the swollen pulvinus at the petiole base has lost turgor, making the leaves hang down
I went for a walk yesterday to look for pigeon-wood fruit (Hedycarya arborea) in the Birdwood Reserve near the Zealandia sanctuary. The understory was very dry and many plants were wilting noticeably.
Coprosma grandifolia wilting badly
Everywhere, the soil was dry and dusty. But the wilting was most intense on the little ridges that run down the steep valley sides (this valley runs along the Wellington Fault). Interestingly, out in the open, some of the same plants showed no wilting at all. Maybe those ones are acclimated to dry conditions.
Hangehange (Genisotoma ligustrifolium) leaves are dull and wilted.
What's going on? Is this global climate change?
These fern (Microsorum pustulatum) leaves were dull and wilted, with a slightly silvery sheen.
It might be, but this year is also a very strong El Nino year. Of course the strength of the El Nino might itself be due to climate change. But in general, it's tricky to extrapolate from an extreme weather event like a hot or cold day, or even a hot or cold season, to overall long term climate trends. If we don't allow people to say a snow-storm is evidence that climate change isn't happening, we shouldn't allow people to say a heat wave is evidence that it is.
Kawakawa (Piper excelsum) starting to wilt. The leaves have curled and are hanging down.

However, long term trends show pretty clearly that the climate is getting warmer almost everywhere, and it seems that last year, and this one so far, are way warmer than even that trend would have predicted. You'd have to be pretty out of touch not to have seen the evidence in the form of temperature graphs in the news or on line.

Anyway, locally and for now the good news is that today the rain is here, and it's cold. I don't know if this rain is a drought-breaker, but with the cooler seasons approaching I guess we can expect more of it.

Did I find pigeonwood in fruit? Yes, thanks; I did.
Pigeonwood (Hedycarya arborea) fruits.

How long will it be before I start complaining about the rain and cold?

Sunday, 5 October 2014

The Great Veronica Hunt—part 7.

Spring’s here, although you wouldn’t know it today in Christchurch. I’m here for a couple of days to collect and photograph three veronicas for the eFlora project: Veronica polita, V. lavaudiana, and V. hederifolia. I've seen the last two on previous occasions, but I've never seen V. polita before, and it hasn’t been collected in a while, so I went after it first.

Most of the recent collections are from Riccarton, a suburb of Christchurch, but even so, they’re not very recent. In 1954 it was found in the grounds of Mona Vale, a stately home that now belongs to the City Council. In 1966, it was collected in Puriri Street, nearby. And in 1974 it was found on the other side of Riccarrton Road at the Riccarton Town Hall’s car park (now the Riccarton Service Centre of the Christchurch City Council). I went there first.

The car park is still there, but the old hall and much of the garden area is behind mesh fencing, such a feature of contemporary Christchurch. This is because of earthquake damage that still isn’t repaired. I poked around without success and then moved on. At this stage, it was a mild morning and I was enjoying seeing Riccarton on foot. It gave me lots of opportunity to look into little weedy patches of waste ground, flower beds and so on. One passer-by offered me a cigarette; he thought I must be scavenging for discarded cigarette butts—after all, what else could a grown man be doing groveling among the weeds.

I stopped for a coffee and hastily put on my waterproofs as a cold front swept through, and headed off up Mona Vale Road. Alongside the railway there was plenty of Veronica persica and V. arvensis, but nothing that looked like V. polita.

At Mona Vale I knocked on the door of the gardeners’ lodge, where they were very helpful. Brian showed me the likely spots, especially where a long length of brick wall had fallen down, and is now colonised by Kenilworth ivy, Cymbalaria muralis. We didn’t find any V. polita and I felt guilty keeping Brian out in the pouring rain, so I carried on alone. And then, in the part shelter of a low box hedge beside the rose garden, there it was.

V. polita is very similar to V. persica, but it has a smaller, darker flower, and a smaller, rounder, and hairier fruit. I’ve put a couple of pieces out by the window to see if a flower will open.

The pedicels are strongly recurved at fruiting, and there's a tuft of hairs at the base of the calyx, also seen in V. persica. The capsule has rounded lobes; they're spreading and rather triangular in V. persica. This one's got a tooth on the side of one calyx lobe, which is a bit unusual.

Tomorrow I'm off out to Banks Peninsula to look for V. lavaudiana, and to pick up some V. hederifolia at Lincoln on the way.

Wednesday, 26 March 2014

Wednesday Wildflower: Oenothera acaulis

When I was a little kid, I loved the Hans Christian Andersen story of the ugly duckling, a cygnet—teased by the ducklings for its ugliness—that turned into a beautiful swan.  This wildflower reminded me of that story.
Oenothera acaulis leaves (the left one with a seed capsule attached to the leaf axil)

Oenothera acaulis sprawls across the ground; its weak stems can't seem to stand up straight.  Its leaves are wrinkly and untidy, and look a bit like the leaves of many weedy plants.  But when its huge white flowers open just as the sun is setting, it's a transformation.
An Oenothera acaulis plant in flower.

The flowers stay open for a day, then they turn pale pink and wither.
Oenothera acaulis flower.

It's not strictly a wild flower in New Zealand, but a few people cultivate it.  I got some seeds from the Christchurch Botanical Gardens for research on seed dispersal.  It has established in my garden and this year's plants have come up of their own accord from seeds in soil where I planted it last year. Some botanists would count that as wild, but it's not the definition we used in Flora of New Zealand Vol. 4, where crossing a boundary (such as into the neighbor's yard or onto the street reserve) was needed.
Oenothera acaulis old flower withering and showing the 150 mm long floral tube.

Anyway, these huge flowers open so quickly at sunset you can watch them moving.  It's a beautiful sight.  The style is very long and sits inside a long floral tube.  The pollen has to grow all that way to reach the ovary.
Oenothera acaulis: this old flower has turned pink as it withers

My interest in O. acaulis began years ago when I grew some in Christchurch.  I'd been working on the ice-plant family Aizoaceae and I noticed that the capsules of O. acaulis were stumpy and woody; they looked more like the capsules of Aizoaceae than the usual long and slender Oenothera capsules.  So I wondered if they opened the same way.
Oenothera acaulis unopened fruit.

Most Aizoaceae have an unusual method of capsule opening; it's called hygrochasy. Hygrochastic capsules open when they're wet. Most ice plants live in the deserts of South Africa and Namibia, and wetting their capsules causes special tissues, called expanding keels, to swell. The expanding keels are attached to a non-swelling resistance tissue and their swelling generates curvature in the capsule walls that forces the capsules open.  Other ice-plants have more complex add-ons that help to splash the seeds out of the capsules using the energy of falling rain-drops.

So I picked a couple of Oenothera capsules and dropped them into a glass of water. Within 15–20 minutes they opened fully. That's a fairly slow rate of opening, but it's about what the ice-plants do. It's thought to be a mechanism that ensures they won't open until enough rain has fallen to enable the seeds to germinate and establish.
Oenothera acaulis cross section of a capsule

Oenothera capsules don't have expanding keels, but they do have four spongy internal walls (bright and pale above), and running up each of their four sides is a rigid woody vein (brown above).  The spongy walls swell when they take up water and the rigid vein constrains the swelling to force the capsule open.  In the enlarged photo below, the rigid vein is on the right, characterised by rows of thick-walled cells; the cells of the capsule's internal walls are spongy and can expand when they're wetted.
Oenothera acaulis cross section of a capsule, enlarged, and viewed under polarised light and filters to show cell arrangements and thickened walls.

This is the only time I've been scooped in my research, because while we were writing the paper about this, German botanist Hans-Dieter Poppendieck published a thorough account of fruit opening in O. acaulis (Poppendieck 1995).  He also came to this through noting the similarity with Aizoaceae.

Like the ice-plants of Africa, O. acaulis is also a desert plant, but it's from South America.  It's a remarkable example of parallel evolution, where the same function has evolved twice in unrelated plants, and the two plants have achieved the same result in ways that are structurally very different.

Also, this is a plant that can move, both when its flowers open rapidly at dusk and when its fruits open on a rainy day. It's the "ugly duckling" of the plant world.


Poppendieck, H.-H. 1995. Hygrochastic capsules in Oenothera (Onagraceae). Mitteilungen aus dem Institut fuer Allgemeine Botanik Hamburg 25: 99–115. 

Thursday, 6 March 2014

Wednesday Wildflower: Viola banksii

In New Zealand we have three native and 5 naturalised violets.  One of the naturalised ones is from Australia, identified in the 1988 Flora as Viola hederacea.  It's occasionally cultivated, and because it's stoloniferous it tends to spread and occasionally escapes to become naturalised.  So I was delighted on a trip to Australia last December to see a similar plant growing in the wild, in the hills inland from the Sunshine Coast.
Viola banksii in the hills near Maroochydore, Queensland
I took some photos, and posted this one on Facebook, but my Melbourne University friend and colleague Michael Bayly politely suggested that this plant is more likely to be Viola banksii.  It seems Viola hederacea is a complex of several species and it has been divided up fairly recently.  I just tucked that information away in my mind and carried on.  Incidentally when photographing that violet, here's the view if you stand up and turn around to face the other way:
Glasshouse Mts, Queensland.
Last weekend I was out walking and saw what looked like the same violet growing in a suburban garden in Wellington.  It was overhanging the footpath enough that I deemed it permissible to steal a little bit to photograph and to grow on in the garden at home.
Viola banksii, cultivated, Karori, Wellington, New Zealand.
Using the key Mike recommended and a recent paper in Austrobaileya (Little and Leiper 2013), I was able to satisfy myself that this is indeed V. banksii and not V. hederacea.  It doesn't necessarily mean the naturalised one is the same species though; I'll have to check the specimens next time I visit the Allan Herbarium at Landcare Research.

Little, RJ; Leiper G, 2013.  Viola perreniformis (L.G.Adams) R.J.Little & G.Leiper, stat. nov., with notes on Australian species in Viola section Erpetion (Violaceae).  Austrobaileya 9: 80–101.

Monday, 10 February 2014

The Day We Fight Back

Websites all over the world are protesting today (11 Feb 2014) about surveillance of the internet, email, telephones, and other communications by government agencies of the USA, UK, Canada, Australia, and New Zealand. Most are carrying a banner. I have joined the protest in spirit, but I couldn't figure out how to paste in the code that would generate the banner on my blog, so instead I'm writing this explanation and putting in a link here that explains the protest and its aims.

For New Zealanders, I note that one political party has already promised to repeal the latest spy legislation and to close the Waihopai spy base.