# Wood versus Dirt Berms



## Summit Ridge Guy (Aug 16, 2010)

Not sure if there is a "right" answer but we are in the process of re-doing a trail out at Summit Ridge to make it more fun and flowy. We will have some bigger corners that will require some berming. Some of the guys have suggested a wooden wall ride/berm rather than dirt. Looking for some feedback since I also have the land manager role also and want a feature that is sustainable and safe. In the northwest it rains 10 months out of the year so I am not sure how slippery a wooden wall ride would get.

I would assume from a builder perspective dirt is more forgiving compared to dialing in a wood structure?


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## JDM (May 2, 2008)

I've built some smaller berms that are fully sunk into the ground (think full-bench). Getting the drainage right is important, but it is reasonable quick and holds up well.

I helped out on a local trail network on a berm with a rock base structure and dirt on top to sculpt. It is a lot of work, but it will last. See pic below (I don't know the rider).

I've ridden some all-rock berms. They weren't very high, but they rode well and were really works of art. That method requires a ton of skill and time.

Wood seems like it invites trouble.


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## Ridnparadise (Dec 14, 2007)

Wooden wall rides = intimidating whereas dirt berms = encouraging to the average rider. Having said that, if you cannot armour a dirt berm enough because it is on an off-camber or outsloped bit of hill, it may be vulnerable to traffic, break up or get braking ruts whereas a wall ride would not. Wall rides are a buzz with practice though.


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## Fattirewilly (Dec 10, 2001)

A wood feature will require more maintenance/inspection than a dirt feature. The wood is more applicable in a limited use/advanced level trail.


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## cmc4130 (Jan 30, 2008)

http://forums.mtbr.com/trail-building-advocacy/need-help-wooden-berms-setup-739784.html


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## mtbikernc69 (Mar 23, 2004)

Fattirewilly said:


> A wood feature will require more maintenance/inspection than a dirt feature. The wood is more applicable in a limited use/advanced level trail.


Not if you build right and sturdy. I stopped building dirt berms because I had to go back every 2 years and add more dirt to them. Actually I'm not a huge fan of man made berms anyway. Where's the skill in riding a bermed corner as opposed to a flat or off camber corner?


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## Skookum (Jan 17, 2005)

mtbikernc69 said:


> Where's the skill in riding a bermed corner as opposed to a flat or off camber corner?


It's usually involved in the theme of the trail.

Has not much to do with skill as it does with speed.

What "type" of experience are you trying to provide.

As far as sustainability on a high traffic trail there is nothing worse than an outsloped off-camber turn. Eventually riders sluff them out by skidding, and they look and ride terrible. Off-camber turns are usually built by and for hikers, they are not considering how wheels react with the tread.

Over accentuated berms are fine on a trail that is appropriate for free-ride, racing, flow trails etc. But you have what many of us bikers have ridden on in multi-user trails built by and for hikers as mt. biking is relatively new. There is a novelty of riding tech tight off-camber corners and there is a developed low-speed stall trials style riding technique to them, but there are also technique in how to ride a berm too.

Summit Ridge Guy, if you build them out of wood, always build leaning a bit bigger and steeper than you think, as it's always easier to build backwards by shaving or trimming posts etc, if you don't get it right.

edit, really this is a really good way of building a bermed wooden corner imo. You can use this same design and make it a bit larger and steeper depending on the corner. 
http://forums.mtbr.com/trail-building-advocacy/sweet-looking-switchback-copper-harbor-754346.html


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## thumpduster (Nov 19, 2008)

mtbikernc69 said:


> Where's the skill in riding a bermed corner as opposed to a flat or off camber corner?


There's plenty of skill needed to ride a berm with speed.

Off-camber corners are a sign that something wasn't done right in the initial design or build of the trail; these are probably one of the most ackward trail features to ride and- as Skookum aptly points out- one of the first to show disproportional wear. Certainly in the turn, but also in the "skid zone" going into the turn.


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## pnj (Dec 15, 2008)

dirt rules.









but with knobby tires, people skidding and really wet conditions, wood is a great alternative. with large tires, the wood can be rough cut/textured to prevent it from getting too slick when wet.


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## DOCRIGID (Sep 16, 2009)

pnj said:


> dirt rules.
> 
> 
> 
> ...


yes it does! amazing work.


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## cmc4130 (Jan 30, 2008)

i have noticed that when dirt is damp it is still tacky/sticky, but with the same level of moisture, the wood features do become slick, even with grating... however that itself is not quite the problem. the issue is that you need to make sure that the wood/lumber turn is banked at the appropriate angles. whenever your bike is leaning at the appropriate angle and matches up with a berm/bank, then traction isn't an issue--you'll stay on it, even if it's wet. but if the wood bank/berm is at either a mellower or steeper angle than the ideal lean-angle of your bike, that's when you're going to slide out (either bottom side or top side slide out...)

for example, although the wood/lumber features at Keystone are awesome, there were several times when i felt like the angles were not right for the turns being required. it was wet and i saw several riders slide off of them. rather than having flat banks, a better approach is concave/bowled shape--although of course that takes a lot more woodworking skills. dirt berms, if built right, do tend to be concave/bowl corner-ish, like in skateboarding...but that's easier to do with dirt.

Keystone:

dirt S berms with transitioned (concave) faces...









flat bank lumber turns with kinda-questionable angles:









this one in particular was a challenge. it's hard to tell from the picture, but this is a serious decline into a very tight turn with very little banking angle. the guys that i saw who had this mastered were experts at controlled skids and slides (it was wet). the grating did not prevent sliding (although prob better than nothing):



















at Winter Park, this one had good angles for the speed :


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## MountianbikeG (Dec 29, 2011)

Dirt all the way, i build lots of trails and put in 10 hours of work atleast every weekend on mine, only built bridges with wood but they seem to tedious to maintain as burms... dirt holds up and is fun for riders of all levels


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## MtnMan1 (Aug 25, 2011)

pnj said:


> dirt rules.
> 
> 
> 
> ...


I have PBRs and a shovel. please let me hang out with you guys.


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## Ridnparadise (Dec 14, 2007)

There's berms and berms in this thread. Too many *dirt* berms have wood in them rather than rock and almost none are like the lovely Da Vinci dirt one above. I too want to make it's babies

Coupla things that don't happen on wood berms are sub-surface water invasion after manufacture and massive rainfall erosion, but they can be maintained and the wrong wooden angles cannot. Some of those Keystone pics look like a nightmare.


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## cmc4130 (Jan 30, 2008)

some bmx race tracks use asphalt on the berms/turns . . . .


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## lightjunction (May 17, 2011)

In my opinion, dirt is definitely the way to go if you're looking to make the feature rideable for a wide variety of skill levels. Wood berms are a blast, but they're tougher to manipulate once they're built, and they can look intimidating.


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## Downhill mtb kid (Feb 7, 2012)

Dirt, Easyer to form, lasts longer and is more fun when you go fast into it!


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## 475856 (Feb 6, 2010)

We have both and a well built dirt berm lasts a lot longer. The club down here has used treated wood on the wood berms and they are starting to rot after a few years.
Our climate doesn't help either...High humidity and tropical downpours. 
We use crushed coral-rock/ limestone and this turns to concrete and lasts for years with minimal upkeep. This material is $$ but as the club found out that other MTB parks down here use this and trails last a lot longer without too much work, it was decided to use this DOT material. ( it is used as underlayment for the highways here in FL )
Especially since only the same 10 peeps do 95% of the work.. For clarification this is in a man-made MTB park.
Out in the wilderness, I'd still consider dirt but you have to see how well it all packs together and maybe armoring is necessary to make it last.


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## matbar20 (Jan 30, 2012)

*Dirt*

I find sometimes that wooden trail structures are quicker to build, especially if the equivelant feature in dirt would require a lot of it. But wood wears out, breaks, and needs to be done right the first time as it often can't be easily moved.


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## Mr.Me (Feb 12, 2012)

That rock berm looks amazing! looks like a TON of fun to ride!


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## raisingarizona (Feb 3, 2009)

Rock and dirt > wood.


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## Big C (Jul 21, 2011)

dirt is more fun cause you can shred it


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## M5Tucker (Aug 8, 2011)

We just finished building this on Sunday. We didn't have room to expand the corner radius, and the existing corner was really killing the flow. We would have had to build a massive dirt berm or use pavers to pull off a fun corner otherwise, and the soil in our build area is difficult, either loose & full of duff or rocky, not to mention the drainage problems on a steep sideslope. We still have to build up the base a bit, but it's basically done. I really prefer riding dirt too, but given what we have to work with I think this is a pretty sweet compromise.


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## clockwork (Dec 9, 2006)

Nice wood berm!

I perfer to work only with dirt and rock...I love dirt berms because as trails age flow changes/improves and being able to move an entire berm back or changing angles is cakework ..With wood you get what you build hard to make many if any adjustments. Give me almost any slope/material and I can turn it into one sweet insloped berm with drainage and with a nice grade reversal prior and after. You could poor buckets of water and it would never travel in the riding tread of the corner but would drain after it and before it while also alowing the berm to drain also. .


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## Ridnparadise (Dec 14, 2007)

I think that last wooden berm is a far better option than dirt in that spot and it is built well (I think), but the guy riding it is in trouble. I'm sure it's not completed in the pics, but there is almost no tranny between the boards and the dirt, so commit or die. It's really tight and steep(-sided) and it looks difficult. I'm old enough to doubt being able to bend my neck far enough to see through it to the exit - at least not without an on-site chiropractor. Maybe a 24 incher would hammer it? Pics can be deceiving, I may be wrong and this is not meant to be criticism of that berm so much as an observation of bermology.

What I am getting at is, if it isn't perfect, then how do you make it better?

With dirt you get the tools out and add, re-shape, contour, alter drainage etc as needed. I can do that, but I wouldn't have the guts to build with wood for fear of not getting it right straight-up. How do you test ride as you build? We have a couple of crash test dummies, but they do have some remaining brain

Anyway, heres a berm for ya'll Outlook Wooden Berm And FreeRide - YouTube


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## deezler (Jun 21, 2011)

^ That's AWESOME.


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## 475856 (Feb 6, 2010)

That Berm looks great! :thumbsup:


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## M5Tucker (Aug 8, 2011)

That's a spot on observation from those pics, because it's not done yet 

The rider is Ian, and it's mostly his design & construction. He's also a really, really good rider. That was one of a handful of test runs before we weatherproofed the wood and blocked it off for the week so no one would ride it yet. The transition is being built this weekend, and chicken wire is going on for traction. The finished product (we hope) will be rideable by a wide range of riders, with a passable dirt berm transition to the wall. I'll try to snap some pics of the proper finished product.

The ride-testing part is the bugger about wood, because we basically just have to hit it & hope it works as intended, so a point to dirt for that. In our case there's significantly more planning involved with a wood structure vs. dirt though, and we over-build, almost to a fault.

Thanks for the complements!



Ridnparadise said:


> I think that last wooden berm is a far better option than dirt in that spot and it is built well (I think), but the guy riding it is in trouble. I'm sure it's not completed in the pics, but there is almost no tranny between the boards and the dirt, so commit or die. It's really tight and steep(-sided) and it looks difficult. I'm old enough to doubt being able to bend my neck far enough to see through it to the exit - at least not without an on-site chiropractor. Maybe a 24 incher would hammer it? Pics can be deceiving, I may be wrong and this is not meant to be criticism of that berm so much as an observation of bermology.
> 
> What I am getting at is, if it isn't perfect, then how do you make it better?
> 
> ...


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## Ridnparadise (Dec 14, 2007)

It's pretty obvious he's a good rider and those sort of runs have to happen so you know how it feels for the average rider when they don't get the rhythm. 

When you build up the dirt tranny below the wood, do you put lots of rock around the base of the board platform? Here, even with treated timber the bugs would eat and spit it out in a couple of years if the wood was buried. 

With our building, we have noticed that visual clues can make a huge difference to the line and confidence of line riders choose. When we have a tight section, apart from clearing vegetation to allow vision, we put trail clues down. Like moss covered rocks embedded that act like a runway. You can also sometimes fool the eye with such clues to take the line into "the line" you know works best entering or leaving a berm. We sometimes use drainage to do that between exit and entry to the next corner. In your corners the clues could be painted on the wood as well as in the soil.

I'm sure that corner will work really well


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## Laffinatcha (Feb 24, 2012)

Dirt dirt dirt all the way.


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## Ridnparadise (Dec 14, 2007)

OscarW said:


> That Berm looks great! :thumbsup:


That whole area is mega. It could easily become a shrine for freeride with a few years of expansion. There is so much in that hillside already that it has to be supported and the local council is so far holding off. Like everywhere the issue is liability, but The Outlook is a place that when you go there and take your first look, you say yes, or f##& no, never in my life. For most it's a spectator spot.

Liability is limited by Darwin. Berms are only a temporary worry up there. Go The Outlook


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## slocaus (Jul 21, 2005)

Ridnparadise said:


> It's pretty obvious he's a good rider and those sort of runs have to happen so you know how it feels for the average rider when they don't get the rhythm.
> 
> When you build up the dirt tranny below the wood, do you put lots of rock around the base of the board platform? Here, even with treated timber the bugs would eat and spit it out in a couple of years if the wood was buried.
> 
> ...


This is early work in progress, after five years of getting approvals / permits. etc. Here are photos that will give you an idea of the area. Rock and dirt are limited, what there is is loaded with eucalyptus duff.
https://picasaweb.google.com/photosCCCMB/TheEucsSkillsParkBuildDayOctober2011


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## M5Tucker (Aug 8, 2011)

The peeler core in the ground is pressure treated and surrounded by rock, and the 2x4's of the decking are all weatherproofed twice, and we placed rock around their bases as best we could before throwing dirt on. That's the wood we had to work with, pressure treated would be preferred. We fully expect to have to re-deck this in a few years, so we'll see.

We're working on the visual cues bit- we joked about painting a big arrow on the wall  The sight lines on this trail are pretty open so it hasn't been a problem that I know of, but for our upcoming trails we'll need to think about it more.



Ridnparadise said:


> It's pretty obvious he's a good rider and those sort of runs have to happen so you know how it feels for the average rider when they don't get the rhythm.
> 
> When you build up the dirt tranny below the wood, do you put lots of rock around the base of the board platform? Here, even with treated timber the bugs would eat and spit it out in a couple of years if the wood was buried.
> 
> ...


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## 475856 (Feb 6, 2010)

Ridnparadise said:


> That whole area is mega. It could easily become a shrine for freeride with a few years of expansion. There is so much in that hillside already that it has to be supported and the local council is so far holding off. Like everywhere the issue is liability, but The Outlook is a place that when you go there and take your first look, you say yes, or f##& no, never in my life. For most it's a spectator spot.
> 
> Liability is limited by Darwin. Berms are only a temporary worry up there. Go The Outlook


That vid is pretty rad. No way I ride like that..
Looks like that for the situation, your wooden berm is the right choice there. I have a preference for dirt too but it has to work for the location you're in.
There is a wood berm where I ride, but it is a disaster at the moment because the radius is all wrong......Dirt won't work in that spot either, but neither does a wrongly built wooden one.
It is on the, long, list of things to repair....:smallviolin:


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## M5Tucker (Aug 8, 2011)

double post


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## M5Tucker (Aug 8, 2011)

A little vid of our own, taken yesterday after working on the transition. Still needs more dirt, but it's rideable. We're rethinking the railing on the bottom after seeing it thrash tested, but one stipulation of our MOU is railings on elevated structures over 36" high.

SLO FASTA's Ruthless Wall Ryed on the Flying Ewok trail


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## 475856 (Feb 6, 2010)

^^^^^
Sweet Vid and wall !! Looks like a lot of work went into that one..:thumbsup:


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