The plaintiff assigns as error the failure of the trial court to grant the plaintiff’s motion to strike the testimony of the defendants’ expert, Mr. L. C. McClenny. Mr. McClenny based his testimony as to the value of the property before and after the taking apparently on the erroneous assumptions that the City was taking a 60-foot easement, and that the interest taken was *749one 60-foot wide permanent easement rather than a 20-foot wide permanent easement plus a 20-foot wide construction easement. Mr. McClenny testified that the difference in the value of the property before and after the taking was $4,723.00. The jury found that the difference in value was $4,720.00. The plaintiff’s expert testified that the difference in value was $625.00. The plaintiff was clearly prejudiced by the testimony of Mr. Mc-Clenny, and the testimony should have been stricken. Highway Commission v. Matthis, 2 N.C. App. 233, 163 S.E. 2d 35 (1968); Elsevier v. Machine Shop, 9. N.C. App. 539, 176 S.E. 2d 875 (1970); Morrison v. Walker, 179 N.C. 587, 103 S.E. 139 (1920); and Robbins v. Trading Post, Inc., 251 N.C. 663, 111 S.E. 2d 884 (1960). Furthermore, the trial judge did nothing to correct the erroneous assumption in his instructions to the jury. We therefore grant a new trial.
We do not deem it necessary to consider the plaintiff’s other assignments of error as they may not occur on retrial.
New trial.
Judges Hedrick and Baley concur.