Canto 3 -
Araṇya-kāṇḍa
Chapter 26: Rāmacandra Destroys Dūṣaṇa and his Followers
Text 3.26.31

तैर्मुक्तकेशैः समरे पतितैः शोणितोक्षितैः।
आस्तीर्णा वसुधा कृत्स्ना महावेदिः कुशैरिव॥

tair mukta-keśaiḥ samare patitaiḥ śoṇitokṣitaiḥ
āstīrṇā vasudhā kṛtsnā mahā-vediḥ kuśair iva

taiḥ = with those; mukta-keśaiḥ = their hairs were dishevelled; samare = in the battle; patitaiḥ = who had fallen; śoṇita-ukṣitaiḥ = and they were stained with blood [all over]; āstīrṇā = was strewn; vasudhā = land; kṛtsnā = the entire; mahā-vediḥ = a great sacrificial arena; kuśaiḥ = [strewn] with kuśa grass; iva = like.

Like a great sacrificial arena [strewn] with kuśa grass, the entire land was strewn with those who had fallen in the battle. Their hairs were dishevelled and they were stained with blood [all over].

The object of comparison here is kuśa grass because too many [night-rangers] had fallen in the forefront of the battle.1

1 Rāmāyaṇa-bhūṣaṇa: raṇāgra-patitatvātiśayāt kuśa-sāmyoktiḥ.