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Length 16 miles
Time 4 hours
Total Climb 2900 feet
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Jackson Demonstration Forest (Double Loop)

Something about the demonstration forests of CAL FIRE seems to make them particularly good for mountain biking. In that respect, Jackson Demonstration State Forest lives up to the standard set by Soquel Demo Forest and Boggs. As far as I understand, Jackson Demonstration Forest hosts most if not all of the trails people mean when they rave about mountain biking in the Mendocino area. Jackson is a large forest with miles and miles of trails none of which are closed to bikes as far as I know, and many of which are singletrack ranging across a broad spectrum of technical difficulty and fun. This particular ride was my first sampling of the riding in this area and is the kind of ride that could serve as a representative example to others of what can be expected here.

My main source of information for this ride, and in fact my primary source of information about biking in the Mendocino area in general is the trail guidebook Mountain Biking the Mendocino Coast and Beyond as well as any morsel of online resource made available by the primary person behind that book, Roo Harris. Unfortunately, this is not a book you could hope to pick up by simply walking into an REI or searching on Amazon. Unless you're lucky enough to find one available through Mendocino Bike Sprite, you can only hope to order one directly from Roo Harris through the NorCal Forum on MTBR.com when he announces a new printing there. (His username there is "RooHarris".)

While on the topic of sources, a quick note about trail names: The trail names I quote on this page are based on the information in the book mentioned above. The book is not too precise about where a particular trail ends and the next one begins. I've tried to do my best in interpreting what's shown there, but the trail name I use for any particular spot on the ride may not always be correct.

Incidentally, I remember reading a source mentioning that trails at Jackson Demonstration Forest are signed. If you are told that, take it with a grain of salt. There are plenty of trail signs, but not in all the places where you need them. Unless this has changed since the time I'm writing this, anyone unfamiliar with this area who attempts to get by solely based on trail signs while doing this ride will most assuredly get lost before too long. In fact, I find this ride difficult to navigate overall. The only way I imagine a first-timer can follow this route successfully on their own would be by using a map-displaying GPS that's showing the track of the ride. What I would strongly recommend to any unfamiliar rider who doesn't own a GPS receiver and is thinking of trying the ride on their own would be to either find locals who know the area and get them to guide you, or buy a GPS.

This particular ride follows one of the more popular routes at Jackson Demonstration Forest, as far as I understand, and comes with its own nickname: Double Loop. To be precise, this route is titled "Double Loop Redux" in the guidebook I mentioned above, implying that it's the modified form of an earlier route variation called "Double Loop". The book explains that this version "avoids Camp 2 and Dining Hall" by using a new series of trails. I couldn't tell you what that means exactly, but the information available online convinces me that this route now is what people commonly understand as the "Double Loop".

The distance of the ride location places it near the threshold of feasibility for a day trip, in my opinion. My drive time from San Francisco was just over three hours when there was no traffic. Considering the likelihood of encountering traffic at least on the way back, this would place the round trip drive time somewhere in the ball park of seven hours. So, an overnight stay might sound preferable to some folks, especially considering the presence of the lovely town of Mendocino nearby. Given the distance from the Bay Area, one reasonable question would be whether the ride is worth the drive. If you're going to be spending, say, a weekend here anyway and will be doing other things in addition to this ride, the answer is an easy "yes". For someone coming here solely for this ride, the value proposition might be tougher. The singletrack on this particular route is mostly low-technical-difficulty, first-class singletrack, but the majority of the mileage of the ride does not provide anything superior to any good singletrack at Skeggs Point or Camp Tamarancho, for instance. Only limited segments of the ride are of a truly special character. So, for someone who hasn't yet checked off all other Bay Area ride options from her list, I couldn't recommend that this ride be prioritized higher than those. However, if most other good ride locales closer to the bay are old news to you, then this ride does deserve to be on your list, in my opinion, especially as the first-day ride of a mountain biking weekend at Jackson Forest, perhaps. Having said that, this is only speaking about this particular ride route. For all I know, there are more juicy options tucked away in other corners of this forest that would put the widest grin on the face of any advanced rider.

The route mixes together fire-road segments and a wide variety of singletrack trails. While there are certain sections where tree roots are fairly prominent, the trails on the ride are not terribly technical, as I already mentioned. Rock gardens on this route are almost non-existent. However, there are still plenty of trail features to keep advanced riders entertained including repeated up-and-down undulations, many tight (sometimes very tight) twists, very tight hairpin turns, and occasional sharp dips. To me, the only noticeable type of biking difficulty on this ride was posed by a few stretches where the trail becomes very narrow while traversing a steep hillside, feeling a bit exposed.

Parking is available at the trailhead, though I'm not sure I'd consider it a piece of cake. There is no formal parking lot at the entrance used for this ride. The closest thing to that is a small space for head-in parking against a log fence. That could fit about five or six cars. There is a smattering of other roadside clearings in the immediate vicinity that look suitable for parallel parking. However, it's not hard to imagine that space availability might get a little tight on popular days. On the positive side, there were no signs along the road to the trailhead of restrictions or parking enforcement of any kind. So, any nook into which you can squeeze could probably be used for parking. However, there are some residences right around the trailhead, so we should all be careful not to abuse their pockets of parking or block their driveways. Incidentally, there is no "Jackson Demonstration Forest" sign for which you can look to know that you've arrived at the right place to park. The best indication you can look for is a road sign mere feet from the trailhead announcing that "Pavement Ends" and a smaller park sign that announces "Horse Camp" right at the spot the paved road transforms into gravel, which is about the spot where the ride begins. My recommendation is to carefully study the first few of my photos linked on the left to familiarize yourself with what the trailhead looks like, if you'll be trying to find it on your own for the first time.

Since a large part of this route consists of a loop, one question worth asking is the direction in which the loop should be traversed. In the case of this particular ride, this has an easy answer: clockwise. Not only is this the way in which the loop is described in the guidebook from which I've taken it as well as a handful of GPS tracks I saw online, but it's also the self-evidently better way of doing the loop since it results in a ride where the fire roads are mostly ridden uphill or flatly and the bulk of both major descents are done on singletrack trails.

The trail on which the ride begins is called Parallel Action. This trail begins in a very promising way. The first half mile or so of this trail very playfully twists, turns, dips, and rises, all while throwing at you various concentrations of tree roots to keep things interesting. This portion of the trail feels like an amusement park ride for mountain bikers. Things change when this half-mile segment is over, though. I would still qualify the remaining mile and a half you travel on this trail as singletrack, but it's much straighter, much flatter, and frankly not very interesting. If this segment is not merely and old dirt road that's narrowed-down during its use as a trail, then it must be a singletrack that enjoyed much less inventiveness in its design. I have to say that it's a bit better in the return when you can maintain a higher speed thanks to an imperceptibly gentle downhill slope in that direction, but I'm not sure that's enough for its redemption.

Parallel Action is followed by a segment on Little Lake Road (Road 408), which is a wide dirt road. Only a few hundred feet after you turn onto this road, the ride follows a bypass that's picked up on the left, but it's not a big deal even if you miss it, because this bypass seems to reconnect with the same wide road in less than a quarter mile. You leave Little Lake Road at one of the few well marked trail junctions on the ride, where a sign announces "Forest History Trailhead". Forest History Trail is a fun singletrack, but your stint on this trail is a short one. In a quarter mile, you turn onto Manly Gulch Trail. This is the trail on which you will be doing your first long descent in this ride. In comparison with Forest History Trail, Manly Gulch is a smooth forest singletrack with fewer trail features, unless you count a few switchbacks and a couple of small, wooden bridges. It's a fun-enough, twisty trail that descends across the hillsides of this gulch that are steep enough to deserve its name, but interesting trail surface features is not on the menu for this one. It is, however, on this trail that I encountered the first spots on the ride I found a bit exposed, where this trail was traversing some of the steepest parts of the steep hillsides.

Near its end, Manly Gulch Trail widens into a smooth fire road shortly before it drops you onto Thompson Gulch Trail (Road 730) near Thompson Gulch, which seems to contain a concentration of campgrounds. Almost immediately after you turn left onto Thompson Gulch Trail, you turn right to get off it. This is where you pick up the trail that a trail sign announces as "Nature Trail". You start out on this trail by first crossing a creek. There wasn't much water in the creek bed at the time of my ride and that might not be an exception, judging by the shortness of the simple wooden bridge that was there for pedestrians to cross the wet part of the creek bed. After continuing flatly for a very short while, you start the first of the two sustained climbs of the ride on Ripper Trail by turning right at the first junction you encounter. This one-mile climb is a serious one where you gain about 550 feet, but much of the elevation gain happens on nice singletrack and the climb includes only a few spots where the slope reaches unreasonable levels of steepness. Riders in good shape won't worry too much about this one. On your way to the "top", you will follow Eagle's Roost Trail and Old Jeep Trail, but the turns are easy to follow: simply keep heading uphill. Even when the trail splits into two near the top of Eagle's Roost, both sides rejoin before long, though using the left-hand singletrack option as represented on this page results in a gentler climb.

At the end of that second climb, you end up on Steam Donkey Trail. With the exception of a singletrack bypass shorter than a quarter mile that the route uses, this trail is a fire road, although it's an "aged" one: it's partially narrowed down by vegetation and it has a single well worn biking line, meaning you ride much of this trail following that narrow line, essentially as if you were on singletrack.

After doing that for about a mile and a quarter, the second major descent of the ride begins in earnest when you turn onto the singletrack Big Tree Trail. I could say that riding down Big Tree Trail is both eventful and mellow at the same time. The trail is a narrower-than-usual singletrack that snakes playfully along a hillside that's extra steep in some places (the hillside is; usually not the trail). These are also among the parts of the ride where I felt the trail was a little exposed. Other than that, however, it doesn't have many surface features that would make it interesting; it's a smooth singletrack partially covered in cushy duff. So, in that sense, it's on the mellow side. However, it does descend a staircase on the way down, which is an unexpected "event" you don't encounter on most trails. The stairs are too steep to be ridable by mere mortals, but they have some space on the side that could allow them to be bypassed (though I would say that riding the bypass wouldn't be the best thing to do in terms of the sustainability of the trail). At the end of the descent, Big Tree seems to dissolve into a confusion of trails meeting in a flat area. This is easily the most confusing spot on the ride in terms of the difficulty of navigation. I don't have any good directions for those who will try to make it through this spot without a GPS or a guide who knows the way. You need to "kind of head toward the left and kind of ahead" after the trail first emerges into this confusion. Look through the couple of photos at the link on your left that follows that area to know what to look for in order to know you're on the right track. Finally, Big Tree Trail also forces you to cross a crumbling bridge before it's done with you, which is the second thing that qualifies the trail as "eventful", in my opinion. This is the kind of bridge that one would have significant qualms about carrying a bike over. The drop to the stream below is only about 10 feet, but even that's enough to be unnerving as you step across this short bridge with rotting substructure and wobbly planks.

A short and flat fire-road segment (another gravel forest road, really) follows this. The next segment of singletrack arrives fairly soon, but it starts at a junction that's easy to miss. Boiler Trail begins on the right-hand side just at the point where you encounter a yellow metal gate. For a little over a quarter mile, this trail seems to follow the remnant of an old flume. The existence of an old boiler here, from which the trail seems to get its name, also points to the kind of industrial use for which such a flume may have been built. This flat singletrack stretch shortly changes into a singletrack climb. If I'm reading the guidebook correctly, this climbing portion of the trail is named Fury III. The slope is not excessive at under 11% in average grade, but the trail occasionally seems like it was built over a series of barrels laid on their side. It has no shortage of small humps. These probably make the descent of this trail a real hoot, which may be the inspiration behind naming it "Fury", but they make the climb a bit tougher.

When the singletrack portion of this climb ends, it continues in the form of a fire-road climb on Road 720. This signals the beginning of an easier grade for the rest of this final extended climb on the ride. While the slope of this road briefly exceeds 10% grade in one segment, it stays at or below 7% for most of its length. That should have made this dirt road one of the breezier segments of the ride, but an unexpected factor placed this among the least fun portions of the ride for me: this is one busy dirt road! I can name plenty of paved roads in the Bay Area that have less traffic than this road. It felt like my lungs never had more than a minute or two of reprieve between the dust clouds kicked up by the tires of the cars and trucks that drove by.

The next junction on the route marks the end of the last extended climb as well as that of the last fire-road segment of the ride. The only problem is that this is an unsigned junction too, though this particular one is at least easy to give directions for: Gas Cap Trail will be a singletrack trail that starts off the right-hand side of the road just when the climb ends and the road becomes almost completely flat. If you find yourself starting to descend gently on this segment of dirt road, you've missed this turn. Gas Cap Trail will initially have you pedaling a little bit, but the bulk of this half-mile singletrack is spent in a gentle descent that loses nearly 150 net feet of elevation. This is a sweet and twisty—though unremarkable—singletrack. The singletrack segment that immediately follows this one is far from unremarkable, however. The aptly named Confusion Hill Trail and its continuation, More Confusion, start at yet another easy-to-miss junction. If you find yourself back on a dirt road after little more than half a mile of singletrack riding here, then you've missed this junction; go back and look for what would have been a right turn shortly before emerging onto that road.

The "Confusion Trails" are easily the highlight of this ride, in my mind. For nearly a mile and a quarter, this stretch of singletrack twists, turns, dips, and rises so tightly that it seems to be making a concerted effort to make full use of every square feet of the forest floor. There aren't many technical features along this stretch that stand out in my memory, unless you count some tree roots, but there is no shortage of tight squeezes that might cause trouble for riders with extra-wide handlebars, or opportunities for low-speed bike handling and track-stand training. It's not exactly a recipe that lends itself to good flow, but it does make the trail feel like a playground built for nothing but the amusement of mountain bikers. There are even a few stunts along the way, like a couple of log rides and a few jumps; all with a bypass available. Along with the very first half mile of the ride, this segment is part of what stands out in my mind as the portions of this route that make this ride really worthwhile. I have to point out, though, that these portions of the ride could also be experienced as part of a much shorter and "more concentrated", seven-plus-mile ride route known as Jiro's Playground.

More Confusion Trail ends by dropping you back at the first junction on the ride that was with a dirt road where the loop portion of the route had begun. When you're doing the ride for the first time like I was, it probably won't be immediately obvious to you when you reach this junction again which way to go in order to return via the trail you originally used for getting there from the beginning. If you head toward the right, past the wide center of the intersection while looking to your left, you'll quickly spot the entrance of that trail, starting with a short dip.

One thing that partially hurt the enjoyment of this ride for me was the prevalence of mosquitos. This is not exactly a rarity on any Bay Area trail on the kind of warm July weekend on which I've tried this route, of course. However, I don't remember too many warm Bay Area rides where the sheer density of the mosquitos were worse than this. In most parts of the ride, I was almost immediately swarmed by numerous mosquitos as soon as I stopped for any reason. For those who can be particularly bothered by this, it's one significant factor to be kept in mind.

Another thing I'd like to add is about a temporary trail closure in this area that might be of interest to those who are thinking of altering this ride route. You may see signs about this closure near the beginning of Forest History Trail on this particular ride. Don't let that confuse you; it doesn't affect this particular route. It may be relevant to those who are interested in taking Forest History Trail instead of Manly Gulch Trail down to Thompson Gulch Road, but even those riders may still use the "East Side" of Forest History Trail as of June 2015 (unless the dates were changed); only the "West Side" branch of the trail is closed through the winter of 2015-2016. You may find a map of the closure on the forest's website.

Finally, probably no discussion of biking in the Mendocino area should be considered complete without covering Mendocino Bike Sprite. This is an outfit of mountain bike guides and ride organizers, to say nothing of their advocacy for trails and mountain biking in this area. Roo Harris, whom I named in relation to the guidebook I discussed above, happens to be part of this group. So, if nothing else, we have the best ride guidebook for this area to thank them for. If I were a rider interested in trying out this ride or others in this area without having to worry about navigating with a GPS, I would give them a call first.

© Ergin Guney


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