It happens again and again that one finds red pustules on trees or bushes. This is a fungal disease called Nectria.
Dead branches are affected first
Even if it doesn't look particularly dangerous, you should act quickly. Because the fungus first attacks branches that have already died, but then quickly works its way to he althy areas. Especially when the plant is weakened, the fungus has an easy time. It attacks the branches of wounds found in the bark.
Cut off the affected branch - but not on the compost!
If you now discover such red pustules on your trees, there is only one thing to do: Cut off the affected branch and put in the organic waste. Never on the compost, as the fungal spores can spread here and get back into the cycle. If several branches are already affected, all must be cut off. If necessary also radically. If the bush or tree is otherwise he althy, it will sprout again. Nectria most commonly affects fruit trees, maples and currants.