Friday, December 2, 2016

Guilty pleasures (the up-side of invasives)...

("Invasive" wildflower display between Cromwell and Alexandra, New Zealand) [All photos by Jan Fahs]

Like all good conservationists, I like my nature pure. I would just as soon only see native plants in most landscapes (with the minor exception of city gardens and of course vegetable and cereal producing areas to feed us--and I suppose some pastoralism in there's getting more complicated). But what happens when the invasives create gardenesque sweeps worthy of a painter? Can we make exceptions for these?

Proof I was in New Zealand last month (is it last month already? feels like yesterday still the impressions are so bright) and here Jan (whose pictures I'm using throughout this post--mine weren't as good)  has caught me in the act: we both took way too many pictures.

Of course, its mostly red valerian (a.k.a. Jupiter's beard: Centranthus ruber) which has naturalized many places on the planet. I have admired this blooming wild in Greece, where it seems to almost always be a chalky pink: here every shade from pure white to deep crimson can be found. Along with California poppies (Eschscholtzia californica) and a goodly number of other Mediterranean introductions. All of them exotics and all of them planted with such cunning and care you'd swear it was a garden.

The environmentalist angel on one shoulder is fuming with anger and indignation: how could such horrible invasives be tolerated? There is another fallen angel, on my other shoulder whispering ("Aaaah, isn't it pretty?"). I have some friends who have only one angel, who can look at this and not suffer some qualms and indecision: if I were given a magic wand, would I "whoosh" away all the invasives and restore exactly what was there prior to European settlement? Or should we go back before the Maoris as well (they must have had an impact too, don't you think?)...and would that restored landscape persist with rabbits, hares, possums and so many other plants that are probably responsible for the success of what you see more than humans by ourselves.

Have I mentioned the lavender you've been seeing is Thymus vulgaris?  This was much the commonest weed, growing so thickly that it's harvested by the ton for herbal extracts. There is a minor industry of herbalists who rely on the plant itself, and legions of beekeepers who bring their hives here: how does the thyme on this hill differ from alfalfa in a pasture (or paddock as they say in New Zealand?)...

I believe this is Salvia verbenacea. And there were legions of Mignonette (Reseda luteola, I believe, although only R. alba is listed on the Department of Conservation's weed list) and other fellow travelers here and elsewhere...

Excuse me while I admire this unholy landscape. I guess we may all share a little of the sublime hypocrisy of those pious evangelistic preachers who bellow fiercely on the pulpit, but wallow in sin when parishioners aren't around. A stretch of a comparison, I know!

A last few lingering looks...

Our salvia again...such tracery!

Just a little more red and pink, please!

I'm incorrigible, but you're still looking at it too aren't you?

We wind down with some thymes...

Scotch broom by the acre (abetted by agricultural practice and logging)

Everything you see in this picture is exotic: the Eurasian grasses, the broom and the distanct plantation of Monterrey pines: in fact there is barely a stitch of native vegetation anywhere on the eastern quadrant of New Zealand below, say 1000 feet (more or less)... That said, there are a few remarkable reserves throughout the country (even at lower elevations) and a high level of awareness among every New Zealander I met about the ecological issues and challenges they face. I believe the horticulturists especially are extremely self-conscious and have borne the brunt of the pain of the draconian laws meant to prohibit new weeds: any new plant to cultivation in N.Z. must be submitted to a Government process costing tens of thousands of dollars--a very regressive and self defeating example of colossal myopia and ineffectiveness in my opinion. Makes me root for the weeds, frankly!

It may be an ecological menace, but it's beautiful!

New Zealand plantspeople can't obtain the latest Podophyllums from China legally (plants that are never posing a threat to anything but pocketbooks of plantsmen)...but they are free to pave their lawns (and countryside) with invasive Eurasian grasses, and topiaries. I rather liked these in the Southlands!

I shall quit while I'm sorta ahead...
The issue of weeds is a sticky one at best: I have gained enormous new insights thanks to this island country. New Zealand delighted me no end with her fantastic beauty, the rugged (and often weed free) high country and unbelievable alpine cushion plants and wildflowers...the astonishing (and largely weed free) temperate rain forests I sampled all too briefly ih the far south and west coast. The amazing private gardens where exotics and native plants were grown to perfection, and two of the best public gardens I've ever visited (Christchurch and Dunedin Botanic Gardens)...I hope I might have a chance to go back again--hopefully leading a tour in January 2018 for the American Horticultural Society! Meanwhile I shall savor every moment of one of the most magical trips I've ever taken in my life (weeds and all!).


  1. One of the things that seems to be ignored when discussing invasives is that so many of them are beneficial to bees, hummingbirds and other fauna. I bet the hummingbirds (if New Zealand has them) were going wild for those hillside Centranthus blossoms and ditto the bees on the Thymus blossoms. Perhaps if a savvy group of volunteers were to assemble and deadhead the flowers once they're finished, it wouldn't take more than a few hours and it would assure that the plants didn't take over the entire island. That hillside is magnificent and beneficial to humans and critters. That's my two bits anyway. :)

  2. Your post made me think of the following paragraph.

    "Another pestiferous alien that plagues local forests is garlic mustard (Alliaria petiolata), now the dominant spring flower of many woods. Europeans used the plant as a seasoning, and may have brought it with them for that purpose. In any event, garlic mustard was first noted in the United States in 1868 and has thrived ever since. The first record of the species for the region and state occurred at Ravinia, Lake County in 1918. Since then, in Illinois at least, "the rate at which new populations were detected approximately doubled every ten years."

    A Natural History of the Chicago Region, Joel Greenburg, pp. 104
    taken from Nuzzo (1993a, 30,31; 1993b)

    Unfortunately, it is impossible to predict which species will become invasive. The question then becomes ... if you had the choice would you rather New Zealand be filled with diverse native species or a few introduced species that dominate everything else? Would you even visit New Zealand if the only plants that could be seen were invasives?

    This is the dilemma we face with our preserved land in the Chicago Region (USA). If something is not done about the problem of invasive species then no one will want to visit preserves and public support for their continued protection will erode away.

  3. I appreciate your comments, James: and fundamentally agree: There's a huge patch of garlic mustard spreading in a shady slope of Cherry Creek not far from my house--I didn't think it would tolerate our dryness, but it does. The issue of "invasives" is so very complicated: some plants are here to stay and relatively harmless: but when island ecosystems have been so compromised, as they have in New Zealand, the prospect of restoring natives is beyond the beyond: what it really boils down to is what the community demands in terms of land use and how many resources can be expended, and how many people care. At this point, the only real efforts expended are to use round up along roadsides and to restrict access to germplasm for horticulturists--both of which I believe cause more damage than the potential 'invasives'...not sure where we should go from here. Meanwhile, we might as well enjoy the pretty ones! (The ugly ones usually do the most damage and no one talks or cares about them)...

    1. The determination of whether something is pretty or ugly is qualitative. Many of the Chicago Regions worst invasive plants were brought here because people found them to be horticulturally desirable. Undoubtedly some of the invasive species in New Zealand arrived by the same manner.

      The use (and misuse) of herbicides is a heated topic. Without herbicides much less could be done about the problem of invasive species and many people would give up altogether on doing anything.

      Restoring native species is possible. In the Chicago region hard working people, most of whom are volunteers, make progress every year. There are no quick fixes in restoring native vegetation, but it can be done.


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