The hills have a smile! Around the US, fall brings cooler temperatures and the promise of changing leaves – but in Polk County, Oregon, the autumnal season also heralds the arrival of a massive smiley face made of trees. Every year, the happy symbol can be spotted by drivers travelling on Oregon 18 between Grand Ronde and Willamina. As for how the smiley face got there in the first place, Hampton Lumber company spokesperson told that the symbol was designed and planted on the company property in 2011. "After every harvest, our foresters start planning the reforestation process," Kristin Rasmussen explained. "They typically plant a variety of native species depending on the elevation and soil conditions, including Douglas fir, western hemlock, noble fir and western red cedar." As for its distinct colouring, the smiley face was created by larch trees, which "turn yellow and drop off in the fall," per the company spokesperson. "Which is why the smiley face is best visible this time of year," said Rasmussen. Although the smiley face won't necessarily be part of the fall foliage forever, the spokesperson said that it should be visible for the next 30-50 years – then it'll be time for the trees to be harvested.