Vegetation response to slash walls that exclude deer from hardwood forest regeneration harvests.

Slash walls were developed at the Cornell University Arnot Teaching and Research Forest in 2017. Slash walls have proven effective to exclude deer. Annual measurements of permanent sample points have documented changes in vegetation inside versus outside of slash walls. This presentation will review 4 to 6 years of vegetative response, inside younger and older slash walls, to assess their association with the regeneration stocking, hardwood seedling diversity, seedling height growth, and other metrics of response. The design and construction of slash walls will be reviewed.
Presented by Peter Smallidge at the noon session on February 22, 2024. Coauthors include: Brett Chedzoy, Paul Curtis, and David Weinstein.

[@jmarcleclerc]

Great research work. The mention of brush walls sparked my interest because I have been using my hedgerows to keep sheep (300) within a desired paddock. Last fall, after leaf drop, they discovered there was not a coyote on the other side so my system for giving them one paddock at a time fell apart. My question: Any numbers on dimensions for brush walls? I have lots of slash material within hedgerows. Thank You.
Jean-Marc Leclerc

[@ForestConnect]

Hi Jean-Marc - Thanks for the note. We built the slash walls as a test of concept to see what the brush walls look like with the materials at hand. Because it had no value, we asked that all possible material be added to the brush wall. We did not give any specifications on brush wall dimensions, but because the loggers had just finished building slash walls to 10 ft height, the brush walls looked similar though with smaller and less resilient materials. We have pictures of coyotes inside our slash walls, so I doubt the brush walls would exclude coyotes. Best, Peter Smallidge

[@anemone104]

Interesting video. Especially the 8 deer per square mile. I'm working on woodland management/ecology in southern UK and I wish we only had 8 deer per square mile. That's another story.
At 10:23 you say that Cornell are interested in carbon sequestration (by forests) I paraphrase. But trees don't sequester carbon, only store it. The proportion of forest carbon that enters sequestration via geological processes is vanishingly small. Are they sure? Maybe watch this and read the blurb for an explanation: ua-cam.com/video/ZadE0OWwtWY/v-deo.html

[@brianjonker510]

What is your educated guess as to how detrimental deer impact regeneration of hardwoods in a more typical area of patch work farm fields, pastures and forests?

[@ForestConnect]

@brianjonker510 - I'm sorry, but I'm not able to offer much of an educated guess. There are too many variables in play. If you're in NY I can say that I rarely, if ever, see hardwood seedlings that have not been browsed by deer. Alternative food sources, such as farm crops, may just help sustain a larger deer population. I suggest you walk about and look for evidence of browsing, talk with your local forest/wildlife agency, or install some plots as described at AVIDdeer.com

[@TheAcenightcreeper]

Is the benefit worth it since slash adds considerable amount of fuel for wildfires

[@ForestConnect]

Yes, the benefit is worth it. In the Northeast the risk of wildfire is not zero, but is quite low. In the future we plan to measure wood moisture content and relative humidity at different heights in the slash wall. Prior work at the Arnot Forest by colleagues found that brush piles have higher levels of both than in adjacent open ground. While the slash walls have more fuel, that fuel might be less flammable than it appears. Between the low fire risk regionally, our suspicion about fuel characteristics, and the success of slash walls excluding deer, our nod is towards using slash walls.

[@anemone104]

Can't say in a US context, but my own experience working with coppice in Dorset, Hants and Surrey (roe deer plus very large numbers of introduced sika and a few introduced muntjac) is 'huge'. We don't have general hunting over here, so the deer population is very large and expanding - roadkill corpses are common and the effects on seedling growth and regrowing coppice can be catastrophic. They will kill coppice and those trees may be centuries old and make seedling growth negligible as well as having huge effects on ground flora. I wish we only has 8 deer per square mile! Our woodlands are predominantly patches in long-established farmland. Predominantly small, some (like the one I work) are ancient. Which is not to say 'old growth' as that's vanishingly rare over here.
I use dead hedges to exclude deer from the regenerating coppice. These are basically hand-built laid barriers around 8' high and using much less material than the ones seen here. All material is less than 3" diameter. Anything greater is own-use firewood. I work by hand as machinery is 1) uneconomic at the scale (1/2 to 1 acre a year) 2) inappropriate to the scale of the woodland if utilised at 'economic' scale, 3) causes unacceptable damage to ground flora and coppice stools. This is a different system to 'clear fell and re-grow'.
Dead hedges work well if big enough. They last around 3 years as effective of themselves and maybe another couple in conjunction with dense regrowth either side. BUT coppice is re-cut at around 7 years - the product is small material. The majority of the cut material is removed (sold) so there is no material to re-create dead hedges. Without fencing and the current deer population densities, the coppice will fail in year 8 and following. Dead hedges in this context are a one-shot tactic. If you want to know more, click on the anemone icon and go for a rootle in my content. You'll have a lot of stuff to look at. Maybe start with this: ua-cam.com/video/11UnVArLn7A/v-deo.html This vid is unfinished, but it'll give you the basics. As an independent ecologist, I don't have resources to allow me to put the time in that I'd ideally like to the info' (video) on the channel (which is unmonetised). Hope this was some use to somebody.