Lush tropical hammocks, great birding, and a dash of history along the mangrove-edged waters of the Indian River Lagoon make Oslo Riverfront Conservation Area a diverse and interesting place to explore.
Ferns and wild coffee grow to enormous sizes, bromeliads dangle like chandeliers in the forest canopy, and unusual fungi sprouts from rotting logs in the forest floor.
Add trails that seem to vanish into the thick undergrowth, and a sometimes-confusing maze of mosquito control canals and embankments along the lagoon, and you have yourself an afternoon’s worth of adventure.
Location: Vero Beach
Length: 2.4 miles or more
Lat-Long: 27.587051, -80.375452
Fees / Permits: none
Bug factor: moderate to annoying
Open sunrise to sunset. Mosquitoes can be fierce at times; use plenty of protection. There are now two trails at Oslo Riverfront Conservation Area – this hike focuses on the original trail system.
The shorter South Trail system can be accessed a little farther down Oslo Road on the right.
From Interstate 95 exit 147, Vero Beach, head east on SR 60. At the intersection of US 1 and SR 60 in downtown Vero Beach, head south 3.8 miles. Oslo Road (CR 606) is at the traffic light in front of the South Vero Beach Square Shopping Center. Turn left at the light, and left into the trailhead after two openings on the left – one for the shopping center, the other the exit from the trailhead. The small parking area easily fills up with visitors’ cars, so use the shopping center parking as an alternative.
At the kiosk at the entrance to the trail system, grab a map and set a GPS point. While the trails – at least in the tropical hammocks – are generally well signposted, the trail system in the mangrove marsh is not.
The hurricanes of 2004 trimmed back the once sky-blotting canopy, but the impressive height and girth of the trees that rise above an understory of marlberry and wild coffee (look for coffee beans in October) will have you looking up.
Marked as the “Herb Kale Nature Trail,” the entrance trail is a bit springy and sometimes mucky as it passes beneath tall palms and large oaks.
After crossing a boardwalk through a fern-filled marsh, you reach a fork in the trail. At the fork, keep left and cross the bridge.
Keep left at the next fork, too. While it’s tempting to keep looking up – the tall, slender cabbage palms and ancient oaks are mesmerizing – don’t forget to look down, too, to see the colorful wildflowers and fungi.
At least twenty rare botanical species are known to be in this hammock, including coral-root orchids and whisk fern.
At the next trail junction, turn right to head towards the mangrove tower. Beyond a clump of silver-tinged saw palmetto, the trail climbs out of the tropical hammock and into pine flatwoods with a sandy floor.
Slash pines tower over the footpath, but the real delight is along the edge of the habitat, the canopy of live oaks filled with orchids and bromeliads dangling giant airplants overhead. The trail enters a scrub forest briefly.
Passing a turnoff to the Pine Flatwoods trail on your left, continue straight to cross a bridge that marks the transition into the mangroves.
You’re on a small island dominated by slender cabbage palms and damp earth, where giant leather ferns add a primordial feel. A salt breeze stirs the palm fronds. The land beneath your feet can get very sticky and mucky when the Indian River Lagoon rises over its banks and saturates it.
Crossing the next bridge, you’re now into the mangrove swamp. Here’s the reason you have that mosquito spray handy. Many years ago, the University of Florida Medical Entomology Laboratory made this their outdoor lab, where students study how mosquitoes transmit diseases.
These mangrove-lined dikes and their adjoining canals are a maze, a puzzle, and it’s easy to get lost along these twisty little passageways, all alike.
Your GPS will come in handy if you want to explore beyond the observation tower, since the dikes double-back, curve around, and hit dead ends.
To find the observation tower, turn right as you come off the bridge. Passing a kiosk, turn left at the next trail junction, where a sign points you towards the observation tower.
It’s less of a tower than a very long ramp, but that makes the birding from this vantage point so much better. Well above and overlooking a large mangrove-lined impoundment, the observation tower lets you watch osprey and herons landing in high branches, ibis and roseate spoonbills feeding on the mud flats, and smaller herons lurking along the edges of the water.
At the base of the observation ramp, there are several choices for where to go next.
(1) To return without exploring the mangrove maze, head straight ahead to the T and make a left. Make the next right, and you’ll quickly return to the bridge back to the main part of the preserve.
(2) To make a loop around the impoundment you just visited, immediately turn right on the causeway between the mangroves. Details provided below.
(3) To wander far afield in a northerly direction between many more impoundments, head straight ahead to the T and make a right. This option will add 1.5 miles to the length of the hike. Keep right at each junction, and you’ll loop around numerous mudflats en route to the northern edge of the preserve, where the trail straightens out and follows an old road. Be sure to make the left where forest meets mangroves at the end of the straightaway to stay within the mangrove impoundments, and keep right from that point on to loop back around to the entrance kiosk and bridge back to the main trail system. Turn right to exit the impoundments.
Of the three options – and we’ve done them all – option 3 provides the best birding opportunities, but option 2 is the most scenic. As the causeway veers to the right, you catch a glimpse of the Indian River Lagoon through the dense thicket of mangrove on the left.
The trail continues to swing right, coming up to the canoe dock. The footpath transitions from grassy to sticky underfoot as you come up to an observation platform which makes a nice bird blind under the mangroves.
In the distance, you can see the tower. Leaving the platform, make a right and follow the loop back around to the kiosk and bridge. Turn left to exit the impoundments.
Meandering back along the trail beneath the palms, the salt breeze eases and you’re once again into the tropical forest. After crossing the second bridge, turn right at the “Pine Flatwoods” sign.
The trail starts out like a series of balance beams over saw palmetto trunks and can be a bit slippery. You return to the wonderland of bromeliads overhead in the live oak canopy.
Look at the trunks of the smaller trees, and you’ll see tiny air plants growing there too. Steeped in humidity, this is a botanical treasure trove, with ferns coming up to shoulder-height in places.
You reach what appears to be a trail junction, but the trail to the right – which once led to the now-fallen Awesome Pine – has been closed for habitat restoration. Turn left down the narrow corridor to an intersection that seals the loop the main trail. You’ve hiked 2 miles.
Turn right to follow the main trail back around towards the coffee-laden tropical hammock at the entrance. When you reach the Hammock Loop, keep left.
This short diversion leads you through a dense stand of wild coffee, American beautyberry, and marlberry, ending beyond the east edge of the parking lot for a hike of 2.4 miles.