Rampant turf + slow growing "old" grass = looks a mess. What can I do?

[watersign76]

First post in Gardening, please be gentle.

Last summer we had our garden "done". Turf was laid on about 60% of the lawn area, for cost reasons we stupidly asked that the old grass was left in situ instead of turfing the lot. The hope being they would "blend".

Over this summer we have realised we have very green & fast growing grass where the turf was laid, whilst the old grass doesn't grow very quickly and looks a bit brown in parts.

Should they eventually blend? Or should we go for replacing the old stuff, or will I then be posting next year "Old turf + rampant new turf = a mess. What can I do?"

Also the turf is a bit sparse at points, so DH has been sprinkling grass seed down and watering it. However the lawn is now forever cover in birds and squirrels. I am guessing they are chopping on the seed?

Any advice/thoughts pls?
TIA

Re the seed you need to use patch magic by miracle grow, it has stuff on it that IRS don't like. Also you have to make sure any seed makes contact with the earth otherwise it will just sit on top of the old grass and not germinate. You should scarily the old lawn and then add more patch magic to help it fill in. Also make sure you feed the lawn.

A belated thanks for this sherbetpips. We will give it a go.

Thanks