Puzzled Finns have taken to Twitter to post pictures of themselves raking the forest after U.S. President Donald Trump said California should learn a lesson from the Nordic country about how to protect itself against wildfires.

While visiting California's wildfire zones on Saturday, Trump told reporters that Finland spends "a lot of time on raking and cleaning and doing things" to clear forest floors, citing his discussions with Finnish President Sauli Niinisto.

Niinisto told Finnish newspaper Ilta-Sanomat that he had spoken with Trump about Finland's wildfire monitoring system. He recalled telling Trump that Finland takes care of its forests, but added that raking didn't come up.

Just an ordinary day in the Finnish forest ~ Ihan normipäivä suomalaisessa metsässä <a href="https://twitter.com/hashtag/Trump?src=hash&ref_src=twsrc%5Etfw">#Trump</a> <a href="https://twitter.com/hashtag/forest?src=hash&ref_src=twsrc%5Etfw">#forest</a> <a href="https://twitter.com/hashtag/firesafety?src=hash&ref_src=twsrc%5Etfw">#firesafety</a> <a href="https://twitter.com/hashtag/raking?src=hash&ref_src=twsrc%5Etfw">#raking</a> <a href="https://twitter.com/hashtag/forestry?src=hash&ref_src=twsrc%5Etfw">#forestry</a> <a href="https://twitter.com/hashtag/Finland?src=hash&ref_src=twsrc%5Etfw">#Finland</a> <a href="https://twitter.com/hashtag/Finnish?src=hash&ref_src=twsrc%5Etfw">#Finnish</a> <a href="https://twitter.com/hashtag/CaliforniaFire?src=hash&ref_src=twsrc%5Etfw">#CaliforniaFire</a> <a href="https://twitter.com/hashtag/RakingAmericaGreatAgain?src=hash&ref_src=twsrc%5Etfw">#RakingAmericaGreatAgain</a> <a href="https://twitter.com/hashtag/rakingtheforest?src=hash&ref_src=twsrc%5Etfw">#rakingtheforest</a> <a href="https://twitter.com/hashtag/Suomi?src=hash&ref_src=twsrc%5Etfw">#Suomi</a> <a href="https://twitter.com/hashtag/haravointi?src=hash&ref_src=twsrc%5Etfw">#haravointi</a> <a href="https://twitter.com/hashtag/mets%C3%A4palot?src=hash&ref_src=twsrc%5Etfw">#metsäpalot</a> <a href="https://twitter.com/hashtag/rakingleaves?src=hash&ref_src=twsrc%5Etfw">#rakingleaves</a> <a href="https://t.co/YOKA3D6C2K">pic.twitter.com/YOKA3D6C2K</a> —@pyryluminen

Hundreds of Finns posted under the Twitter hashtag #rakefinlandgreatagain, many posting pictures of themselves in the forest or their gardens with rakes.

"Anybody needs their floors raked?" tweeted NBA team Chicago Bulls' Finnish star Lauri Markkanen with a picture of him holding a rake.

In Finland even small kids rake forests.<a href="https://twitter.com/hashtag/raking?src=hash&ref_src=twsrc%5Etfw">#raking</a> <a href="https://twitter.com/hashtag/finland?src=hash&ref_src=twsrc%5Etfw">#finland</a> <a href="https://twitter.com/hashtag/forestrake?src=hash&ref_src=twsrc%5Etfw">#forestrake</a> <a href="https://twitter.com/hashtag/rakefinlandgreatagain?src=hash&ref_src=twsrc%5Etfw">#rakefinlandgreatagain</a> <a href="https://t.co/1eG7sJdLqM">pic.twitter.com/1eG7sJdLqM</a> —@ATFuru

A #RakeAmericaGreatAgain hashtag also sprang up on the social media site.

The remains of 77 people have been recovered after California's deadliest wildfire, with almost 1,000 people listed as missing.

Trump took to Twitter just over a week ago to blame a recent spate of fires on forest mismanagement.

Three quarters of Finland's territory is covered by forests and the forestry industry accounted for 20 per cent of all exports in 2017.