Decreasing the distance between node labels and connecting lines in forest

Question

I use the following code to produce trees like the two left ones in the figure.

\documentclass{minimal}

\usepackage{forest}

\forestset{
sn edges/.style={for tree={parent anchor=south, child anchor=north,align=center,base=bottom,where n children=0{tier=word}{}}}, 
background tree/.style={for tree={text opacity=0.2,draw opacity=0.2,edge={draw opacity=0.2}}}
}


\begin{document}

\begin{forest}
sn edges
[S
  [NP [er\\he] ]
  [NP
    [Det [das\\the] ]
    [N [Buch\\book] ] 
  ]
  [NP
    [Det [der\\the] ]
    [N [Frau\\woman] ] 
  ]
  [V [gibt\\gives] ]
]
\end{forest}

\end{document}

I would want to decrease this distance so that it looks like the tree on the right (drawn with tikz-qtree). Is there a way to do this (and set it as a default)?

Answer 1

Do you want something like

l sep-=<some length>

which will reduce the distance between tiers by <some length>?

The following compares the default with reductions of 1em and 2em respectively:

\documentclass{standalone}

\usepackage{forest}

\forestset{
sn edges/.style={for tree={parent anchor=south, child anchor=north,align=center,base=bottom,where n children=0{tier=word}{}}},
background tree/.style={for tree={text opacity=0.2,draw opacity=0.2,edge={draw opacity=0.2}}}
}


\begin{document}

\begin{forest}
sn edges
[S
  [NP [er\\he] ]
  [NP
    [Det [das\\the] ]
    [N [Buch\\book] ]
  ]
  [NP
    [Det [der\\the] ]
    [N [Frau\\woman] ]
  ]
  [V [gibt\\gives] ]
]
\end{forest}
\begin{forest}
  for tree={
    l sep-=1em,
  },
sn edges
[S
  [NP [er\\he] ]
  [NP
    [Det [das\\the] ]
    [N [Buch\\book] ]
  ]
  [NP
    [Det [der\\the] ]
    [N [Frau\\woman] ]
  ]
  [V [gibt\\gives] ]
]
\end{forest}
\begin{forest}
  for tree={
    l sep-=2em,
  },
sn edges
[S
  [NP [er\\he] ]
  [NP
    [Det [das\\the] ]
    [N [Buch\\book] ]
  ]
  [NP
    [Det [der\\the] ]
    [N [Frau\\woman] ]
  ]
  [V [gibt\\gives] ]
]
\end{forest}

\end{document}