وَحَدَّثَنِي عَنْ مَالِكٍ، أَنَّهُ سَأَلَ ابْنَ شِهَابٍ عَنْ الاِسْتِثْنَاءِ، فِي الْحَجِّ فَقَالَ أَوَيَصْنَعُ ذَلِكَ أَحَدٌ وَأَنْكَرَ ذَلِكَ ‏.‏ سُئِلَ مَالِكٌ هَلْ يَحْتَشُّ الرَّجُلُ لِدَابَّتِهِ مِنَ الْحَرَمِ فَقَالَ لاَ ‏.‏

Yahya related to me from Malik that he asked Ibn Shihab aboutmaking a condition in the hajj that one could leave ihram at any placewhere an obstacle befell one and he said, "Does anyone do that?' anddisapproved of it. Malik was asked whether a man could cutplants from the Haram for his mount, and he said, "No." Translation Not Available

Book Ref: Muwatta Imam Malik Book 20 Hadith 959
Web Ref:  Muwatta Imam Malik Book 20 Hadith 262