Hello Ginevra; Well, first of all I'd like to read the skepticism in a reputable journal and I'd like to see it in more than one paper. If you are convinced that the problem is real, then you might want to take that into account in designing your study.

There is a substantial literature on the subject of damaged plants communicating with neighbors via volatile substances. ... or via root contact. So the answer to your question might be subtle.

You don't mention whether your study will be in garden plots or in the field. That might influence your plan. It's complicated stuff! Jim Des Lauriers

@ Ginevra, I think GRASIM is the best model to simulate grazing.

In setting up your experiments, consider that there are differences in animal preferences, differences in plants ability to respond if there is excessive compaction, limits of soil moisture or nutrients, and some plants probably respond better to severe disturbance than others. Grazing intensity can also be a factor, as overgrazed areas can become compacted and plant removal approaching barren conditions. Access to salt and water can locally affect traffic and compaction, erosion. Ideas might be gleaned from range conservationists, soil scientists, botanists on the combination of factors, and a statistician how best to use statistical design to address the specific questions. Since your goal seems to be plant responses to varying levels and frequency of disturbance, perhaps the cutting and removal of clippings will end up being an approach that can be best controlled and measured, and considering factors as soil type, moisture, topography including aspect, plant type and density. Agree with taking time and attention to literature review, plan and design consideration up front.

As you can see from the above responses, the issue is highly complex. Response to grazing is influenced by numerous factors, such as:

- the species composition of the stand

- the kind of grazing animal

- the timing and frequency of grazing or grazing events

- the palatability of the different plant species

- animal preference

- the resulting competitive conditions among the plants

- regrowth and regrazing responses

- the abiotic properties of the ecosystem (eg. Soil texture, soil moisture, drainage, slope, )

- the complexity of the design will contribute to the difficulty of implementation and statistical analysis

My suggestion is to narrow down your goals as much as possible by asking questions such as: is the response of the different plant species to defoliation the most important parameter? You can also eliminate or control some variables based on the ecosystem properties and the currently available research results.

Good grazing!!

Zoheir

I am in William's camp. Also, who are you ultimately trying to inform? Land managers? Ranchers? Conservationists of rare species in grazing lands?

I agree with some of the above . You might narrow your topic to only a few species ( deer, rabbit, bovine, sheep, alpaca , native vs non) to gain a real plan of action on how they effect your goal .

All the best!

Hi, I am sending you a paper that might be useful.

All the best!

Hi Ginevra,

I think that fire can be an interesting possibility. This method is largely employed in projects in grasslands. The biological response (bank seed, juveniles, soil properties, …) for your research is an important point to the final decision. I suggest that you first define the ecological processes that you like to delineate before selecting the method to compare with grazing.

Hi.

It really depends on your goals and the range of the study. Also which animal you intend to simulate. One thing that was not said on the above answers is that the animals' selectivity varies between species or even within the same species, depending on their age, or particular "taste". Also, the grazing intensity affects this selectivity. Animals are more "picky" on lighter grazing, while in high intensity, they don't have more options than to eat whatever is available, so, less selective. I discuss this on this paper Article Long‐term effects of grazing intensity on strategies and spa...

When I was doing my experiment I opt for clipping using a fur trimmer. I wasn't simulating animal selectivity because my aim was to simulate high grazing intensity. Not to mention that simulating selectivity could be very complex. I am happy to see so many ideas on this question!