Cleaning algae, lichen and moss off a wooden gate

[Rollerball]

One of my five bar wooden gates (not the slightly rotting one that I mentioned in another thread) is covered with a thin film of algae, as well as smaller patches of moss and lichen.

I've removed most of these with warm water and a soft brush, although because I don't want to have to re-treat it I'm avoiding brushing too hard, therefore a little algae remains in places.

It was last treated with Osmo UV Protection Oil a couple of years ago and the wood was, I believe, pressure treated prior to purchase.

With all that in mind, and bearing in mind the cleaning, can I get away with NOT re-treating it? The gate is in very good condition, no rot or breaks.

 

[Wayners]

Bleach and hot water.
Stiff brush.

 

[Rollerball]

Thanks, but will it need re-treating?

 

[Wayners]

After washing let it dry and use some wood treatment which will prevent more algae growth.
Unfortunately there is no permanent treatment but a wash over once a year and treat every 3 or 4 years, all will be fine.
I guess its a spot that's perfect for getting problems with moss and algae