- Author: Chris McDonald
As weed practitioners and researchers we work in a field of ‘us vs. them.' There are the plants we want and those we don't. Good weed management can help to ensure a profitable harvest, too many weeds can cause poor establishment in a native plant restoration project. It is also wise to look at the language we use as practitioners of weed management, and ask if it frames our state of mind, especially now that viral information spreads around the world before the truth can get its boots on.
The use of militaristic or adversarial jargon (“target,” “war,” “battle,” “overrun,” etc.) in weed management has been prevalent for decades. Whether the use of these terms is detrimental has also been debated among scholars and practitioners. Several papers were written about the idea of the use of ‘us vs. them' language a decade ago, one of the notable papers being Larson 2005. On the other hand, at about the same time, Coulatti and MacIssac (2004) proposed a neutral terminology for invasive species describing stages of invasion. The benefits and drawbacks along this gradient of ideals have been debated to this day.
A new study measures whether this use of negative language corresponds to a more biased explanation of a study. Warren et al. (2017) conclude that researchers that compare native and invasive species competition in an observational setting reported that invasive species were more competitive than natives when compared to researchers who measured competition with experimental studies. This difference was relatively small (92% vs. 86% of observational compared to experimental studies, respectively). In summary, and if all other things are equal, researchers who observe the effects of a native and a non-native species competing, will overestimate that the non-native species is more competitive 7% of the time. Experimental studies will find somewhat less competitive effects than observational studies.
How does this finding relate to weed management? This is not completely clear; the study was designed to assess the scientific literature, not weed management. One underlying point is that the study does point to the fact that there is an 86% overlap in identifying non-native species as superior competitors. I would argue that is a pretty good success rate and while observational studies may be biased, they are at least biased towards being cautious. Given that there are often few chances to extirpate an invasive species, it should be cost-effective to overestimate the competitiveness for a few extra species than underestimate them and have them spread. Researchers could have been biased on the side of underestimating some invasive species, which I think would be a bigger issue.
As it feels like language is being used more often as a tool to polarize groups of people, it is noteworthy that in our field the negative ‘biolerplate' language used to describe non-native species is declining. Warren et al. (2017) report that the number of papers that use ‘boilerplate' language to describe invasive species as negative has been declining since 2007. They conclude this is possibly a result of invasion biologists self-regulating their language. Whether that will remain for the next decade will also be very interesting.
At the end of the day the weeds do not know they are weeds. On top of that they don't even know! Weeds are stimulated to grow when conditions are right for them, they continue growing as conditions are favorable, and finally they reproduce when they are large enough to do so. We are also pretty good at figuring out what plants are weeds and which ones are invasive. I'm not saying weeds are harmless, they can be extremely harmful. I'm saying it doesn't help me to get angry at the weeds. Maybe the use of ‘us vs. them' language in weed management promotes anger or bias among weed workers, I don't know. I know when I hold onto anger it's like holding a yellow star thistle inflorescence, I am the one who gets hurt.