About the geo-trail: The Tel-Aviv - Jerusalem Bicycle Trail is a 120 km long path connecting Jerusalem (abbreviated in Hebrew as Y-m or Yam) to the Mediterranean Sea (in Hebrew: Yam). If you want to read more about it, you can enter the Yam to Yam Geo-Powertrail: 0 km (GC3TXQD)
The eucalyptus tree was brought from Australia and can be found throughout Israel. This cache is hidden under a big eucalyptus, right off Israel Trail, in the eastern part of Park Hayarkon
Cache location is in the side away from the trail, so that you don't draw much attention. If you need more help, see hint and photo
Back to the eucalyptus, millions of these trees were planted in Israel. At first their mission was to drain swamps, though now it is disputed how much they helped. So many trees were planted, that the arabs nicknamed it "the tree of the jews". Today it is considered one of the most important trees in the country, and is used as a wind breaker, for honey bees, and wood
I heard once in a field lecture in the upper Yarkon that its leaves cause damage to the river, so... But the eucalyptus is such a dominant sight in the Israeli nature, you can't ignore it