I call a spade a spade means I say what I mean.  A spade is for digging and a shovel is for moving coal or snow.  In my family’s folk-lore a farmer used to say, I call a spade a b*****y shovel!

In a rut means having little variety in one’s life.  Ruts are the depressions made by wheels on mud tracks.

As light as a feather is a simile.  A small child may be told, “You’re as light as a feather!”  This is not strictly true.  The opposite is as heavy as lead.  Lead is denser than many other metals.

Clutching at straw is part of a proverb.  Drowning men clutch at straws.  Straw is the dried stem of a cereal crop.  Brewer explains the proverb as:

persons in desperate circumstances cling in hope to trifles wholly inadequate to rescue or even help them.

A clutch of eggs uses the correct collective noun for eggs in a nest.

By hook or by crook means in any possible way.  A shepherd used a crook, which had a hook on the end.  In autograph books a popular entry used to be:

By hook or by crook
I’ll be last in this book.

If the person left too much space afterwards, there might be a competition to see who could be last.

On’t big hook is a dialect expression for on the floor.  If people are too lazy to hang their clothes up on a hanger or hook and just drop them they are on’t big hook.  I came across this in Lancashire.

In the cart means in serious trouble.  Graeme Donald gives the derivation as a condemned criminal’s last journey – in a tumbril.  The Concise Oxford Dictionary explains that prisoners were taken to the guillotine during the French revolution in a tumbrel or tumbril.   A horse and cart in a pastoral scene has no connection with this expression.

Plough a lonely furrow means to manage without help or companionship.  Furrows are the lowest parts of ploughed fields.

To plough a straight furrow is a useful skill for farmers.  It requires concentration and determination.  There are still ploughing competitions in agricultural areas.  Nowadays the plough is attached to a tractor.

In Biblical times a pair of oxen was yoked to the plough.  In Matthew 11:29-30   Jesus invites “Take my yoke upon you and learn from me, for I am gentle and humble in heart, and you will find rest for your souls.   For my yoke is easy and my burden is light.”