In every redwood park, the biggest and most spectacular trees grow on the fertile floodplains next to year-round creeks. These alluvial flats are the crown jewels of the redwoods, and the biggest alluvial flat of all is Upper Bull Creek Flat. It and the adjacent Lower Bull Creek Flat are home to what has been called the world's tallest forest.
This day-long loop takes in almost all of the magnificent Upper and Lower Bull Creek Flats. The pleasant, easy meander includes several of the most impressive redwood groves anywhere.
However, the loop is not perfect; a lot of the trail skirts around the edges of the best groves instead of going through them, and on the north side of the creek the stillness of the redwoods is interrupted by the occasional passing car.
The full loop can only be hiked in the summer and fall because it includes a seasonal footbridge that's normally installed between mid-May (but sometimes not until the end of July) and late September. At other times the creek may still be only a few inches deep and easily forded. When the footbridge is out and the creek becomes a raging torrent, the best alternative to the full loop hike is an out-and-back on the Bull Creek Flats Trail South.
The loop can be started from either end or in the middle at the Big Trees Area. In the summer, the loop can be shortened by crossing Bull Creek on a seasonal footbridge at the Big Trees Area.
The south side of Bull Creek is fairly popular and it's normal to see someone every 5 or 10 minutes. On the north side, the it's rare to see people outside of Rockefeller Forest and the Big Trees parking lot.
Here's the trailhead location in Google Maps.
Bull Creek Flats Trail South starts at Grasshopper Road, where there's enough parking for several cars. The trail begins in an attractive redwood grove but soon climbs onto a hillside with few redwoods. The first mile of the trail, until the Big Trees area, is pleasant if not spectacular. In the winter, it's also slow going because it gets very muddy; fortunately it's the only part of the loop that gets muddy.
The scenery improves dramatically as the trail descends to the Big Trees Area, which is the best part of the hike. The trail winds through the impressive cathedral-like forest, passing two side trails that lead across the creek to the Big Trees Area parking lot. After passing the second of these trails, the trees get a little smaller and the forest less open, but it's a subtle difference and the forest continues to be quite impressive for another mile.
The trail emerges from the redwoods for about a quarter-mile. After re-entering the forest, the trail climbs perhaps 20 or 30 feet up the hillside at the edge of the flat. It remains at that slight elevation, contouring along the hillside for another mile or so. Although the trees on the flat below are quite spectacular, the big old growth stops abruptly at the edge of the flat. As a result this part of the trail is less engaging because you're no longer walking among the big trees, but looking at them from distance. Sadly, the trail actually used to go through the flat but was re-routed onto the hillside.
The trail briefly descends to the flat again but then, in one big switchback, climbs even further up the hillside. Now the trail is essentially in redwood uplands, with no big trees to be seen. This is the transition between Upper Bull Creek Flat and Lower Bull Creek Flat.
Take the first trail to your left, which makes a scenic descent to a smal flat with a very open and somewhat dark old-growth grove. The trail cuts across the flat and crosses Bull Creek on a seasonal bridge.
The north side of Bull Creek is, overall, less impressive than the south, but it still has some exceptional groves.
The Bull Creek Flats Trail North begins to your left just as you enter Rockefeller Grove. Although it's not included in the milage for this hike, I highly recommend taking a 0.6 mile detour and walking around the Rockefeller Loop Trail, which circles around Bull Creek Flat; huge redwoods are especially dense here and the trail is definitely a highlight of Humboldt Redwoods. Traffic noise from Highway 101 is sometimes audible but is not overwhelming.
As it leaves the Rockefeller Loop behind, the Bull Creek Flats Trail North continues through exceptional old growth. There's a break in the redwoods and the trail is briefly squeezed up against Mattole Road as it passes from Lower to Upper Bull Creek Flat. The trail loops around a little flat with some nice redwoods, located between the upper and lower flats. There's another break in the redwoods as the trail runs just below Mattole Road again for a short stretch, then the trail enters Upper Bull Creek Flats. Diving into the redwoods, the trail briefly enters a spectacular cathedral-like grove as fine as any in Humboldt Redwoods.
A few stretches of the trail are very close to Mattole Road and the traffic noise can be annoying on a summer weekend. In contrast, on a winter weekday there might only be a car every 10 or 20 minutes (although in the early morning there seem to be a lot of trucks headed for the Lost Coast) and the presence of the road is not as objectionable.
The flat ends and the trail runs alongside the road for a while; it's advisable to just walk on the road here since the trail is somewhat rough and infested with poison oak. The trail then disappears completely, joining the road as it curves along Bull Creek past a clearing that offers a little sunlight and some very nice views of tall redwoods growing along the creek. There's a dirt parking lot for equestrian trailers to your left. The trail begins again, skirting around the lot and diving into the forest. The trees get noticably bigger as you approach the Big Trees Area parking lot.
Past the parking lot, the trail enters an especially scenic grove. There are glimpses of tapering sunlit treetops and impossibly tall and thin light beige trunks shooting high into the sky. This grove exemplifies the "cathedral-like" redwood forest, with the fluted columnar trunks illuminated by flecks of sunlight filtered through the stained-glass canopy. In winter, the pleasant sound of rushing water permeates the area.
The best scenery continues for about a third of a mile, after which the trail moves closer to the river and skirts the edge of the forest, where the redwoods are much smaller. The Big Trees Trail ends at Mattole Road; turn left onto the road to cross Bull Creek and reach the end of the hike.
© 2007, 2010, 2016 David Baselt