One often hears people say that a weed is only a plant that is growing in the wrong place, but I’ve always thought this is far too simplistic. In any of my gardens past and present I usually prefer to grow native plants, but not exclusively. In any case, I am only really especially interested in growing native plants.
Yeah, but, plants that are native to Australia are not necessarily indigenous to the area, and in this respect I am certainly not very strict. Indeed, having heard lectures by plant epidemiologists on the way that native species are going to have a hard time in their traditional habitats as global climate change creates warmer and drier conditions further and further south on the continent, it may be that plants that have heretofor been indigenous to an area will not be able to cope with (i.e. “adapt quickly enough to”) changing conditions. Hence I feel that experimenting with growing plants that have evolved in different areas of Australia might be a positive endeavour, and that I should keep track of which species thrive and which do not.
Upon showing a local land conservation member the various species I had planted in the plot, many of them Acacias, she pronounced most of them to be weeds. I thought about this, as I knew that her criterion for identifying a weed was therefore that the plant was not indigenous to the area. I could imagine that these non-indigenous native plants were *potentially* weedy, but my own criteria for designation of a weed had to also include their difficult to control spreading.
This block of land, in that respect, I have often labelled a ‘weed museum’, and even though I am not in any way trying to preserve our plethora and variety of what I can confidently label weeds, there are quite a variety of plants here that are not welcome. High on the list of unwelcome and definite weeds are soursob (Oxalis pes-capraeL), capeweed (Arctotheca calendula), nut sedge (Cyperus eragrostis), various thistles, mostly common sow thistle (Sonchus oleraceus), and a couple of types of dock.
However, rather than use the non-indigenous identity as the most salient criterion for designating a weed – lest we categorise the whole of the european descendants of the first invaders of this country ‘weeds’ – I have a number of other elements of a plant’s behaviour and attitude as salutory in declaring their weed status.
Firstly, it is hard to eradicate. I mean, if there are plants in the garden or paddock that one does not want, then if they can be easily eliminated then they can hardly be classed as a weed.
Secondly, and related to their non-ease of elimination status, is their ability to spread. Some plants have evolved to use seeds, some, bulbils, some can regrow from stray stems or rhizomes. Some horror plants use all of these methods. Prolific seed bearers use wind or animal dispersal, and some of these seeds can remain viable in the soil, lurking there, for many years. As they say, one year’s seeding equals 7 years weeding.
Thirdly, their behaviour is in the way of pushing out, strangling, overshadowing, and making life difficult in general for the native or other plants in their vicinity. They out-compete any other plants, and take over.
Fourth comes the matter of aesthetics. Each gardener or tenderer of land will have their own sense of what looks good and what annoys the eye, but the dislike of the form and nature of a plant is one criterion for people to designate a plant as a weed – given that the other criteria are also to some extent met. This particular criterion is my prefered way of translating the saying that began this commentary: a weed is a plant in the wrong place.
And lastly is the criterion regarding the immigrant status of the plant – the archetypal plant in the wrong place, so to speak. But, to my mind, if there is one individual growing out of its indigenous locale, and it does not reproduce, then it can hardly be called a weed.
Unfortunately, upon reviewing all of these criteria, I am unable to get past my earlier observation that the european inhabitants of this country tick every box on my weed identification list.