I am attempting to initialize the values of keys of hashes from a single hash. Instead of all the hashes being initialized by value, the values are all references to the same hash, which I don't want. What is the best way to set up all the hashes with the same structure/values of the one hash without just passing reference? In the example below, I would like the values of hash3 and hash4 to be the key/value pairs of hash1 and hash2. However, what I am getting is the values are being set to references, which means I cannot change the values of hash3 and hash4 independently. 
use warnings;

my %hash1 = (
    bush => "A",
    tree => "A"
);

my %hash2 = (
    dog => "A",
    cat => "A"
);

my %hash3 = (
    plants    => \%hash1,
    animals   => \%hash2
);

my %hash4 = (
    plants    => \%hash1,
    animals   => \%hash2
);

print "$hash3{plants}{bush}\n";
print "$hash4{plants}{bush}\n";
print "\n";
$hash4{plants}{bush}="B";
print "$hash3{plants}{bush}\n";
print "$hash4{plants}{bush}\n";

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In reply to Initial Hash of Hash by value by Anonymous Monk

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