At the coordinates is signage about Poison Ivy to help you identify it. Please take heed, especially if you go on to find GC 5RXK6 or want to go to the beach. Poison ivy grows along the chainlink fence that runs along the (thankfully) wide trail to the different accesses to the beach, so you must be cautious if walking this trail. The warning sign is to help you identify poison ivy so you don't touch it and this info will also help you while hiking anywhere for a geocache.
Learn the phrases: "Leaves of three? Let them be" or "One, two, three? Don't touch me.", as these plants have a cluster of three leaves at the end of a long stem. More identifying indicators of leaves include: three leaflets connected closely together on each stem; the tip of each leaf should be pointy; the leaflets are broad, and the two lateral (side) leaflets are smaller than the terminal (end or middle) leaf; the center leaf usually (almost always) has a small stem, wheres the two side leaves grow directly from the vine/plant and do not have small stems; and the leaves tend to be a bright to dark, sometimes waxy green when viewed from above. In spring, the leaves are usually red, and again in fall they turn red. Poison ivy berries are white or cream-colored and the fruit tends to stay on the plants all through winter and spring. from link http://www.wikihow.com/Identify-Poison-Ivy#/Image:Identify-Poison-Ivy-Step-2-Version-2.jpg
Feel free to post a picture of the poison ivy you see to help others identify it. Thanks.