Your and your debtor's status will be key in deciding if it's worth taking out a CC claim.
If they are a Limited Company, and they are not in or about to enter any kind of insolvency proceedings, you will have a good chance of recovering your money if your claim is successful.
If they are an employed (not self employed) individual and they dispute the invoice, you should be able to recover the money if sucessful. If they own their own home and the value of the debt is high (I think over about £2k), you will have more options open to you.
Unemployed, retired or self-employed - much less likely. You may find the Judge decides they can only afford £5 a week. CC bailiffs cannot levy on goods that are a self-employed person's "tools of the trade". With good reason. If the debtor doesn't dispute the invoice but instead has chosen to ignore it completely (as for the O.P.), they may, as others have suggested, believe that they will be able to get away with not paying even if enforcement is attempted.
The methods of enforcement open to you are:
send a CC bailff round (Warrant of Execution)
ask a CC Judge to make their employer pay you out of their wage (Attachment of Earnings Order)
force them to pay you when they sell their house (Charging Order)
start involuntary bankruptcy proceedings (or winding-up if a company) - if I remember rightly the debt must be >£500, and the Judge will need to be satisfied that they cannot pay their debts
(there is one other "standard" CC enforcement route but I can't remember what it is)
The price was (when I worked in a CC about 10 years ago) about £45 for a WoE, £50 for a AoE, and £500 to begin bancruptcy proceedings. I can't remember what a Charging Order cost. The amount is added to the debt, but you still have to pay it first!
If the debt is big enough you can upgrade the Judgement to the High Court. Their enforces have greater powers (especially when siezing goods). No idea on what this would cost - it seemed to happen very rarely.
A couple of other things: probably best to start the claim in your local CC. If the debtor is a Ltd, the claim should stay in that Court. If they are a private individual, however, and they choose to defend the claim, it will probably be transfered to their local CC.
Disclaimer: info offered to give folks an idea of how the system works, I'm no solicitor and don't know if there have been any changes since I left that particular soul destroying job, and I have smoked a marajuana cigarette in the intervening time, possibly causing irreparable damage to my memory of English civil law proceedings. Get advice if it's big bucks - the Citizens' Advice Beurea was ok for individuals (not Ltds). Also... first you'll have to win the judgement - you will need to prove your case to someone who knows nothing about arboriculture.
Someone said: "i also sent bailiff round but they would not take stereo computer etc unless i payed the storage till sold" - never heard of this. CC bailiff or private debt recovery firm?