This article looks at
wasteful golf courses, which neither make good use of space nor return much to the economy. The author suggests that the land would be better put to housing or business uses.
I will add that a regular park would be more use both recreationally and environmentally. A golf course tends to serve only a few dozen people at a time, and its wildlife value is limited by overgrooming. A park can serve hundreds of people via sport fields, hiking trails, picnic tables, etc. A mix of mowed lawn, unmowed prairie or savannah, and forest plus a pond or creek will host many more species -- especially if landscaped with native plants rather than the exotics favored by golf courses. A nature-minded community could add programs to landscape medians and encourage residents to garden for wildlife, thus creating lines and dots of habitat that would help wildlife move between larger parks.
Here's another article that examines
vacant lots, and low-use properties like parking lots, in high-value areas. The author suggests a land value tax, rather than an improvement value tax, which is one good solution that some cities use.
Another option is a holding fee. If you don't want people to sit on property without doing anything, you can charge them just for doing that. Make the holding fee low if development plans have already been submitted, but high if it's literally just sitting there growing weeds. You can also make it cheaper to hold land for needed development (e.g. a grocery store in a food desert) than for an unneeded development (yet! another! condo!) in your town. Put those holding fees into another area that locals consider important such as affordable housing or small business incubation.
Also, check your
greenspace percentage. Do you have enough
pocket parks? If not, consider reclaiming vacant lots for that purpose too. Especially look at your medium neighborhood parks and large parks that serve the whole town. Are there smaller parks or greenbelts between those that allow wildlife travel? Can you connect the dots to the nearest large wilderness, such as a county or state park, outside of city limits? Have you got a bigger waterfront such as a river or lake? Greenspace surrounding that and connecting it to other parks is a great help.