In (the) first place

In the first place is over-grazing, which caused 35% of land degradation.

Not a terrible ‘error’ - we know what you mean! But still, it’s important to understand the distinction between in first place and in the first place.

In IELTS Task 1 writing we often find ourselves ranking items as follows:

In first place is over-grazing, which caused 35% of land degradation. Meanwhile in second place, 20% of land degradation was caused by deforestation.

But what if you’re listing rather than ranking? Let's say, for example, that you're listing supports for an argument. In this case you need in the first place, in the second place, etc.:

Mr Jones cannot be the one who stole your car. In the first place he was in a different city when the car was stolen, and secondly he is blind!

In this case in the first place means as the first consideration. It's often used to introduce reasons that should be obvious but may need to be emphasised, as in the above example. Notice that it is unusual to continue in the second place, in the third place, etc. Better to switch to secondly, thirdly, and so on.

To sum up..

'In first place..' is useful in Task 1 writing (for ranking)
'In the first place..' is useful in Task 2 writing (for emphasising reasons)

If you're doing this in IELTS Speaking, it can sometimes help you to structure an argument if you count off items using your fingers, perhaps under the table!