DataTemplate Include Another DataTemplate

Question

See below all the DataTemplates have the same first two TextBlock.
In fieldStringTemplate and fieldDateTemplate I would like to refer to fieldTemplate so I am not repeating those two.
How to refer to a DataTemplate from a DataTemplate?

The real application has many more templates and many more common elements.
In the real application these are classes that implement Field.
FieldTemplateSelector is based on the class.

<Window.Resources>
    <local:FieldTemplateSelector x:Key="fieldTemplateSelector"/>
    <DataTemplate x:Key="fieldTemplate">
        <StackPanel>
            <TextBlock Text="{Binding Path=Name}" />
            <TextBlock Text="{Binding Path=DisplayValue}" />
        </StackPanel>
    </DataTemplate>
    <DataTemplate x:Key="fieldStringTemplate">
        <StackPanel>
            <TextBlock Text="{Binding Path=Name}" />
            <TextBlock Text="{Binding Path=DisplayValue}" />
            <TextBox Text="{Binding Path=FieldValue}" />
        </StackPanel>
    </DataTemplate>
    <DataTemplate x:Key="fieldDateTemplate">
        <StackPanel>
            <TextBlock Text="{Binding Path=Name}" />
            <TextBlock Text="{Binding Path=DisplayValue}" />
            <DatePicker SelectedDate="{Binding Path=FieldValue}" />
        </StackPanel>
    </DataTemplate>
</Window.Resources>
<Grid>
    <ListBox ItemsSource="{Binding Path=Fields}"
             ItemTemplateSelector="{StaticResource fieldTemplateSelector}"
             HorizontalContentAlignment="Stretch">
    </ListBox>
</Grid>

Answer 1

It seems to me it would be much better to do something like this:

<DataTemplate x:Key="fieldStringTemplate">
   <TextBox Text="{Binding Path=FieldValue}" />
</DataTemplate>

<DataTemplate x:Key="fieldDateTemplate">
    <DatePicker SelectedDate="{Binding Path=FieldValue}" />
</DataTemplate>

<!-- and so on... -->

<DataTemplate x:Key="common">
   <StackPanel>
       <TextBlock Text="{Binding Path=Name}" />
       <TextBlock Text="{Binding Path=DisplayValue}" />
       <ContentPresenter Content="{Binding}" 
                         ContentTemplateSelector="{StaticResource fieldTemplateSelector}"/>
   </StackPanel>
</DataTemplate>

<ListBox ItemsSource="{Binding Path=Fields}"
         ItemTemplate="{StaticResource common}"
         HorizontalContentAlignment="Stretch">
</ListBox>