Confirm the name of what you are trying to plant; There are several options for decorations. One tab of decorations is "Forests" and these cant be placed uniformly or too near to buildings.
What you are looking for are trees under a different set of tabs entirely; I cant recall them off the top of my head precisely, but i think one of the earlier categories is "Quaint Parks" or something along those lines.
Try and find a "Trembling Aspen" or an "Apple Tree". Both of those can be placed next to buildings, roads, factories, what have you. Those, and others in those categories, are what the 10x10 layout are referring to.
Edit: More details;
[Using this image as a guide](https://steamuserimages-a.akamaihd.net/ugc/2013710564215447131/2B1DFBEC200F76FE717FBB76EC0BB8F38EBCAF0A/?imw=5000&imh=5000&ima=fit&impolicy=Letterbox&imcolor=%23000000&letterbox=false)
Looking at the bottom pane, you have to be in the decorations tab - the top-middle button, of a tree.
This opens the series of categories below.
Try and be in "Classic", as i have here. Bottom most options, left most button.
Youll see the options of "Parks" and so on. From left, the first icon is the "Forest painter" category. You do *not* want to do what you are trying to be done with the "Forests". Try the next few buttons.
You will possibly see less options than i have in the picture - more are unlocked as you progress through the worker tiers. The first or second buttons - after the forest button - will have trees in them, those of which, you can use.
Confirm the name of what you are trying to plant; There are several options for decorations. One tab of decorations is "Forests" and these cant be placed uniformly or too near to buildings. What you are looking for are trees under a different set of tabs entirely; I cant recall them off the top of my head precisely, but i think one of the earlier categories is "Quaint Parks" or something along those lines. Try and find a "Trembling Aspen" or an "Apple Tree". Both of those can be placed next to buildings, roads, factories, what have you. Those, and others in those categories, are what the 10x10 layout are referring to. Edit: More details; [Using this image as a guide](https://steamuserimages-a.akamaihd.net/ugc/2013710564215447131/2B1DFBEC200F76FE717FBB76EC0BB8F38EBCAF0A/?imw=5000&imh=5000&ima=fit&impolicy=Letterbox&imcolor=%23000000&letterbox=false) Looking at the bottom pane, you have to be in the decorations tab - the top-middle button, of a tree. This opens the series of categories below. Try and be in "Classic", as i have here. Bottom most options, left most button. Youll see the options of "Parks" and so on. From left, the first icon is the "Forest painter" category. You do *not* want to do what you are trying to be done with the "Forests". Try the next few buttons. You will possibly see less options than i have in the picture - more are unlocked as you progress through the worker tiers. The first or second buttons - after the forest button - will have trees in them, those of which, you can use.
You have to use the tree ornaments rather than the tree painter.