Arana Gulch is a sea of wilderness butting up against the shores of human activity. Surrounded by housing developments and busy thoroughfares leading to commercial centers, the 67.7-acre city-owned greenbelt is a bustling patch of nature. Blue herons swoop above the expansive oaks, steelhead trout and Coho salmon swim and breed in the creeks, berry bushes proliferate and, less romantically, the Santa Cruz tarplant quietly goes about its struggle for survival against the nonnative grasses that smother it in one of its last remaining habitats.

The tarplant has been the focus of a showdown between the city of Santa Cruz and local conservation activists. That struggle finally lands in court this week, with both sides claiming they have the tarplant's best interests at heart.

The controversy revolves around a section of the Arana Gulch Master Plan proposing the construction of a paved trail system that would be used by bicyclists, walkers and wheelchair-bound nature enthusiasts. The plaintiffs in the case, California Native Plant Society and Friends of Arana Gulch, want this part of the plan axed, and the rest of the plan, including proposals for tarplant habitat protection, kept in place. They argue that the paved trail will have a "significant impact" on the tarplant habitat, and that under the California Environmental Quality Act the city is mandated to come up with a less destructive alternative.

The approximately 12-foot-wide path the city is proposing would connect Broadway and Brommer streets. It would feature observation decks and informative placards on the tarplant and other natural treasures within the greenbelt.

The trail system, if it survives litigation, will stretch for two miles, including paving of the existing north-south trail to allow wheelchair access and the building of a new paved west-east trail connection between the Seabright neighborhood and the Harbor, which will fill in a gap in car-free bicycling routes from the west to east sides of the county. The rest of the trails will be left unpaved for pedestrian-only use.

The plaintiffs believe paving trails and preserving tarplant habitats are two mutually exclusive goals, and, moreover, that the city violated a number of state environmental laws when writing up the plan.

Bill Parkin is representing them and says the lawsuit will result in a "win-win" if the city is forced to cut the bike path out of its Master Plan but keep the tarplant habitat protections.

"Part of the problem is that the city refuses to look at off-site alternatives for the bike trail," he says. "They are going through Harbor District Property for part of the trail. They didn't look at going through more of the Harbor Property to satisfy the need for an east-west bike link. They could connect through Fredrick St. Park, which doesn't have the sensitive areas that Arana Gulch does."

City officials directed all questions to City Attorney John Barisone, who is currently on vacation, but the Master Plan states that the observation decks and trail system must be built in a way that "does not result in significant degradation of habitat values."

The Master Plan also argues that an improved asphalt road will allow the Parks and Recreation Department to close "unauthorized trails" that currently cut through sensitive tarplant habitats.

Fair enough, says Parkin, but the heavy traffic that could result from a bike path, and the fact that the trail will be in close proximity to creek beds, warrants an extra dose of caution.

"Riparian areas are in the coastal zone, and under the Coastal Act they are designated as environmentally sensitive habitat areas," he says. "Throughout the history of this project, the Coastal Commission staff has really asked the city to look at other alternatives to avoid these sensitive areas."

Furthermore, Parkin will argue in court beginning Sept. 7, the decades-old Coastal Act is quite clear in limiting what can be developed in environmentally sensitive habitat areas to resource dependent uses, defined as projects specifically requiring use of the ecosystem in question.

"This allows things like scientific research, a small trail that doesn't impact the species, but would allow people to observe the species," he says. "But it's very limited. An east-west bike plan is not a resource dependent use; it's a transportation use."

However, the city only plans to pave and allow biking on 0.6 of the two-mile trail system throughout Arana Gulch, with one bike path cutting along the bottom of the greenbelt from the Harbor on the east end to Broadway on the west end and a north-south paved trail from Agnes Street in the north to a crossroads with the east-west path in the south. The rest of the trail system would be unpaved and restricted to pedestrians.

The city's Master Plan also stresses in many sections that the trail system and its accompanying displays will increase education on the need to preserve the tarplant habitat. This should cut back on people and their pets accidentally trampling the plant, which is often hidden beneath taller grass, according to the city. In areas of particular concern, fencing may even go up.

Yet conservationists maintain these measures will be canceled out by the harmful effects of cutting down heritage trees, paving the road, and increasing traffic through the fragile tarplant habitat.

Parkin stresses that Arana Gulch is a better-suited venue to protect the tarplant than its other habitats, such as Watsonville's Spring Hills Golf Course.

"If we can't protect [the tarplant] on land already protected by the public, we're certainly not going to be able to protect it on private land where there are certain rights to development," says Parkin. "Therein lies the real problem."

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